Preheat oven to 450°F. Line a medium sheet pan with parchment paper. Spray with olive oil.
Remove the stem and leaves from your cauliflower and slice into quarters (criss cross).
In a small bowl, mix together the olive oil, parmesan cheese, garlic powder, onion powder, paprika and salt and pepper to taste. Brush this mixture on the cauliflower wedges - all sides, except the bottom. Bake covered for 25 minutes, then remove cover and broil to get golden brown tops.
Dressing:
Whisk together the oil, yogurt, lemon juice, garlic, dijon, salt and pepper to taste. If its too thick add in one tablespoon of milk at a time, until you reach your desired consistency. Next fold in the feta and dill. Taste and adjust any flavors if needed. Drizzle on to your wedges along with some optional chili pepper flakes and enjoy!