Preheat oven to 400

Heat a heavy cast iron over medium heat and cook chopped bacon for about 5 minutes, stirring occassionally, until golden

While bacon is cooking, cut brussels lengthwise into about 1/4 inch wide pieces

Once bacon is golden, remove bacon pieces from pan, setting aside on dish and leaving bacon grease in pan

Add brussels to pan with grease and season to taste with salt and pepper. Cook for about 8 minutes, flipping occassionally until all pieces are mostly cooked and have a decent char on them

Add minced garlic and let cook for additional 2 minutes

Turn off heat of stove. Add heavy cream, 1/4 cup of gouda, 1/4 cup cheddar, and bacon pieces to brussels and stir to combine. Once cheese is melted and everything is well incorporated, top the mixture with the remaining 1/4 cup cheddar and 1/4 cup gouda.

Cook in over for about 10-12 minutes until slightly browned on top and bubbly on the sides