Heat cream, 2 Tbsp butter, 1/4 cup Parmesan cheese and shredded cheddar in a pot over medium low heat until cheese has melted.
Add in salt and dijon mustard and stir until combined. Add in precooked, crumbled bacon, if desired.
Once cheese has all melted, add in cauliflower and stir until all pieces are coated.
Place cheesy cauliflower in a large baking dish.
In a small pan over medium heat, melt remaining butter. Once melted, add in almond meal and Parmesan and heat until the mixture begins to brown, about 3-5 minutes. Be sure to stir consistently so it does not burn.
Top cauliflower mac with breading mixture.
Place in oven and cook uncovered for 25-30 minutes. If desired, broil for the last 5 minutes to brown the breading. Be sure to watch closely because the breading will burn.