Hazelnut-Crusted Halibut with Roasted Asparagus

butter

extra-virgin olive oil, divided

halibut fillets, skinned

egg white, lightly beaten

salt, divided

freshly ground black pepper, divided

finely chopped hazelnuts

garlic cloves, thinly sliced

asparagus, trimmed

Cooking spray

chopped fresh thyme

lemon wedges

Roasted Red Potatoes