Preheat the oven to 400 degrees Fahrenheit.
Placed the halved Brussels sprouts into a large mixing bowl and add in the garlic, shallots, olive oil, crushed red pepper, salt, and pepper. Mix or toss the Brussels sprouts until they are lightly coated and the spices are evenly dispersed.
Transfer the Brussels sprouts onto a foil-lined baking sheet. Evenly spread them out on the sheet.
Bake the Brussels sprouts - flipping them once or twice during baking - for 30 minutes, or until they are lightly browned.
Add additional salt and pepper to taste, then serve.