Place the yogurt into a coffee filtered lined strainer and set the strainer inside of a bowl. Cover the top of the strainer with plastic wrap. Place the yogurt in the refrigerator over night or at least 2 hr before use to drain away the liquid and thicken the yogurt.
Preheat the oven to 375℉.
Remove the florets from the crown of broccoli. Rinse them off and dry them on a paper towel.
Arrange the broccoli florets in a casserole dish. Pack them in close together. Microwave on high for 2-3 min until they are fork tender. Remove from the microwave and set aside.
Place the thicken plain non fat yogurt into a mixing bowl. Add the light Miracle Whip, yellow mustard, salt, pepper and ¼ tsp of the garlic powder. Mix everything together and take a taste. Add another ¼ tsp of garlic powder if it is needed. You want to taste the garlic but you don't want it to be overwhelming.
Drop dollops of the yogurt mixture over the top of the broccoli florets. Use the back of a spoon and spread it over the top of the florets.
On a plate mix the fat free shredded cheddar and the Velveeta shreds together. Evenly spread the cheese mixture over the top of the yogurt mustard sauce.
Place the broccoli dish in the preheated oven and bake for 10 - 15 min at 375℉. The broccoli was already fork tender. You are looking to heat it through and melt the cheese on top.
Remove the broccoli dish from the oven when done. Let sit for 5 min and then serve and enjoy. Store leftovers in the refrigerator.
Notes
I used French's yellow mustard. If you want a tangier sauce, you can substitute in spicy brown mustard or Dijon mustard.