How to Make It
Preheat oven to 450°F. Combine butter, garlic, lemon juice, black and red pepper, and 1 teaspoon of the salt in a small microwavable bowl. Microwave on HIGH until melted, about 45 seconds; set aside.
Cook rice according to package directions, substituting broth for water. Fluff with a fork; stir in 1 tablespoon of the butter mixture. Cover to keep warm.
Meanwhile, toss together broccoli, oil, lemon slices, and remaining 1/2 teaspoon salt on a rimmed baking sheet; spread in a single layer. Bake in preheated oven until broccoli is crisp-tender, about 13 minutes.
Arrange shrimp on baking sheet with broccoli. Drizzle with remaining butter mixture. Bake at 450°F until shrimp are pink, about 5 minutes. Serve with rice.