Pesto Pasta with Chicken Sausage & Roasted Brussels Sprouts

fresh brussels sprouts, ends trimmed and any yellowed/browned outer leaves removed, then sliced in half

olive oil, divided

Kosher salt

freshly-ground black pepper

orecchiette (or any pasta)

chicken sausage links (I used spicy Italian), sliced into 1/4" thick coins

garlic, peeled and thinly sliced

pesto

Parmesan cheese, for serving