Preheat oven to 450 F, and line 2 baking sheets with parchment paper.
In a large pot or microwave, steam the brussels sprouts for about 20-25 minutes until they’re fork tender. Allow brussels to drain in a colander until dry and cool enough to handle.
In a small bowl, stir together garlic powder, salt, black pepper, and parmesan.
Use the bottom of a heavy cup or mason jar to smash the brussels sprouts until they're flat, but still holding their round shape. Use a tablespoon to measure 1 tablespoon mounds of parmesan spaced about 1" apart on your prepared baking sheets. Place a brussels sprout on top on top of each mound and press to gently flatten. Repeat until all the cheese has a brussels sprout on top.
Bake for 15 minutes. Serve warm, with aioli if desired, and enjoy!
Notes
Paprika aioli – 1/2 cup of mayonnaise, 2 cloves of minced garlic, 1 teaspoon smoked paprika, and 1/4 teaspoon of cumin — add everything to a small bowl and mix until well combined.