Preheat oven to 450℉.
Heat a Dutch oven over medium heat and cook bacon until crisp. Remove bacon from pan, drain on paper towels, and crumble. Note: Reserve ¼ cup bacon grease.
In a skillet, add ¼ cup reserved bacon grease. Sauté 1½ cups diced onion and 3 tablespoons minced garlic until translucent.
Add collard greens in batches and stir to wilt before adding more.
Once all collards are wilted, add 3 ounces cream cheese and stir until melted.
Once cream cheese is melted, add 16 ounces sour cream, 1 cup mayonnaise, and 3 tablespoons hot sauce. Mix well to combine.
Then add to skillet, 1 cup parmesan cheese, 12 ounces grated cheddar cheese, and crumbled bacon. Stir until cheese melts.
Season with salt & pepper to taste.
Pour mixture into oven proof dish and sprinkle with remaining ½ cup parmesan cheese. Bake 30 to 40 minutes or until bubbly and brown.
Serve with tortilla chips, crackers or French bread.