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Vegetarian spinach stuffed portabello mushroom cap paninis are a great choice for a “meatless Monday” meal. The portabello caps are stuffed with baby spinach sautéed with onion, bell peppers and garlic in olive oil and Italian dressing and mixed with some grated Romano cheese. They are nestled in a low carb Kaiser roll spread with some garlic aioli, topped with tomato slices and shredded fat free mozzarella before being pressed and grilled until the roll is toasted and the cheese melted and gooey.
Spinach stuffed portobello cap paninis can be served for lunch with some fresh fruit. Pairing them with a bowl of soup, a side salad, pasta salad or nice heirloom tomato salad makes a very tasty and filling dinner.
The hubby and I enjoy these meaty stuffed portobello paninis on a regular basis. They are easy to make and flavorful to boot.
Please see the recipe card below for exact amounts and directions.
Ingredient Round Up
- Portobello mushroom caps
- Fresh baby spinach
- Bell pepper
- Onion
- Garlic
- Kraft fat free Zesty Italian dressing or your favorite brand
- Salt & pepper to taste
- Grated Romano or Parmesan cheese
- Light mayonnaise
- Garlic powder
- Olive Oil
- Tomato
- Fat free mozzarella or cheese of your choice
- 647 Schmidt’s Kaiser rolls or bread of your choice
Sodium Alert: The sodium content in this recipe is high due to the brand of Italian dressing and cheese I used. Replacing the Kraft Zesty Italian dressing with Bolthouse Farms Italian Vinaigrette will lower the sodium by 107 mg or Organicville sodium free Italian dressing will lower sodium by 172 mg. Using Good & Gather reduced fat mozzarella from Target will lower sodium by another 50 mg but it will raise the pts. Replacing half of the mayo with plain non fat yogurt will reduce sodium by approximately 80 mg depending on the brand of yogurt and mayonnaise used. All of these changes will lower the sodium for the panini from 848 mg to 611 or 546 mg depending on the dressing used.
Making the Stuffed Portobello Paninis
- Rinse off the baby spinach if necessary and lay it out on paper towels to dry. Blot excess water with a paper towel.

- Rinse off the portobello mushroom caps and remove the gills. Lay the caps on a paper towel to dry off.

- Finely chopped the onion and bell pepper and mince the garlic cloves. Set aside.
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- Bush both sides of the mushroom caps with Italian dressing. Place the mushroom caps on a rack set inside of a foil lined pan.

- Place the caps under the broiler and broil until they are fork tender. Remove the mushrooms from the oven when done and set aside.

- While the mushrooms are under the broiler, heat the olive oil in a skillet. Sauté the onions and bell pepper until they are tender. Add the minced garlic and sauté briefly until it becomes aromatic.

- Add the spinach leaves to the skillet. Add Italian dressing to the skillet to facilitate the wilting of the spinach.

- Transfer the wilted spinach mixture to a bowl. Add the grated Romano cheese and toss to incorporate it into the mixture,

- Make garlic aioli by mixing light mayonnaise with garlic powder.
- Spread both sides of the Kaiser rolls with garlic aioli and place a broiled portobello cap on the bottom half of each roll.

- Place half of the sautéed spinach mixture into each portobello cap.

- Place tomato slices on top of the spinach mixture. Top the tomato slices with shredded fat free mozzarella.

- Place the top half of the Kaiser roll on the sandwich. Place the panini on a preheated indoor grill or panini press. Lower the top and grill until the roll is toasted and the cheese is melted.

Serving Ideas
- Spinach stuffed portobello paninis make a satisfying lunch. You can serve them with some fruit or baked chips.
- These paninis can be served for dinner along with a side salad, coleslaw, broccoli salad, pasta salad, heirloom tomato salad – the possibilities are endless.
- A cup or bowl of tomato soup, Italian wedding soup, cream of mushroom or French onion soup all pair well with spinach stuffed portobello paninis.
WW 7 pt with a 647 Kaiser roll, 6 pt with low carb bread

Equipment
- Cutting board
- Chef knife
- rack
- bowls
- cuisinart grill or panini press
- measuring spoons
- skillet
Ingredients
- 2 large portobello mushroom caps
- 4 c packed baby spinach or 5oz pkg.
- 3 tbsp chopped onions
- 3 tbsp chopped bell pepper - I used an orange pepper.
- 3 cloves garlic
- 2 tsp olive oil
- 2 tbsp Kraft fat free Zesty Italian dressing or dressing of your choice
- 1 tbsp grated Romano or Parmesan cheese - I used Romano.
- 2 647 Schmidt Kaiser rolls or bread of your choice
- 1 tomato, sliced
- 4 tbsp Kraft fat free shredded mozzarella
- 2 tbsp Kraft light mayonnaise
- ½ tsp garlic powder
- salt and black pepper to taste
Instructions
- Preheat the oven broiler on hi.
Garlic Aioli
- Mix the light mayonnaise and garlic powder togethe in a small bowl and set aside. If you wish you can do half mayo and half plain non fat yogurt which will lower the sodium content.
Preparing the Portobello Mushroom Caps
- Remove the stem and gills from the mushroom caps. Rinse off the mushroom caps and lay them on a paper towel to drain and dry. Blot with a paper towel if necessary.
- Take 1 tbsp of the fat free Italian dressing and brush it on both sides of the mushroom caps.
- Line a baking pan with aluminum foil. Place an elevated rack on the baking pan. Place the mushroom caps on the rack, scooped out gill side face down. Place under the broil. Check at 5 min and then every 2-3 min until they are fork tender. Remove from the oven when done and set aside.
Preparing the Spinach Stuffing
- Rinse off the baby spinach leaves if necessary and place on a paper towel to drain. Blot dry if necessary.
- Finely chop the onion, bell pepper and garlic cloves.
- Add the olive oil to a skillet and heat it up. Sauté the onion and bell pepper until they are tender. Add the minced garlic cloves to the skillet and briefly sauté for 30 sec or until it becomes aromatic.
- Add the spinach to the skillet and heat it briefly until it wilts. Most of the olive oil will be gone so add 1 tbsp of the fat free Italian dressing to the skillet to facilitate the wilting of the spinach. The Italian dressing will also add flavor to the spinach.
- As soon as the spinach is wilted, transfer it to a bowl. Add a few shakes of black pepper and 1 tbsp of grated Romano cheese. Toss the spinach to incorporate the black pepper and Romano. Taste the mixture and add salt to taste. I find that the Romano is sufficient to add a salty taste to the mixture but you may like it more salty.
Assemble & Grill the Paninis
- Preheat the indoor grill or panini press. I usually heat my plates to 400℉.
- Spread both sides of the Kaiser roll with garlic aioli. I normally divide a tbsp between the top and bottom of the roll.
- Place a broiled portobello cap on the bottom half of the roll. Stuff the cap with ½ of the spinach mixture.
- Place tomato slices on top of the stuffed mushroom cap. Then spread 2 tbsp of the fat free shredded mozzarella over the tomato slices. If you can spare the points, reduced fat or ultra thin provolone is great on this sandwich.
- Place the top half of the Kaiser roll on the sandwich. Place the sandwich on the grill or panini press. Lower the top plate and grill until the roll or bread is toasted and the mozzarella is melted and gooey.
- Cut the panini in half and serve.
