Shrimp & Broccoli Alfredo

Ingredients:

1½ pounds large shrimp, peeled and deveined

2 cups broccoli florets, steamed

1 cup white mushrooms, sliced

5 garlic cloves, minced

½ medium onion, minced

¼ stick unsalted butter

1 tablespoon ground black pepper

1 tbsp garlic salt