Rinse and cook the rice. Rinse the rice under cool water until it runs clear. In a medium pot, bring the broth to a simmer. Stir in the rice and a pinch of salt, reduce heat to low, cover, and cook until tender, about 12–15 minutes (or follow package directions).
Fluff with a fork and keep warm.
Prep the shrimp. Pat the shrimp dry with paper towels. Season with salt, black pepper, and the smoked paprika. Dry shrimp sear better and taste better.
Warm the pan. In a large skillet over medium heat, add 1 tablespoon butter and 1 tablespoon olive oil.
When the butter foams, add the shrimp in a single layer. Cook 1–2 minutes per side, just until opaque and pink. Transfer to a plate.
Don’t overcook.
Build the garlic butter base. In the same skillet, add the remaining olive oil, then the shallot. Sauté 1 minute until soft. Add the garlic and red pepper flakes and cook 30–45 seconds, just until fragrant.
Keep the garlic pale—brown garlic turns bitter.
Deglaze and brighten. Add the lemon juice and zest, scraping up any browned bits from the pan. Lower the heat and swirl in the remaining 3 tablespoons butter until melted and glossy. Taste and season with salt and pepper.
Combine and finish. Return the shrimp and any juices to the pan.
Toss to coat in the garlic butter. If using peas or a couple handfuls of spinach, add now and cook 1–2 minutes until warmed or wilted.
Serve over rice. Spoon rice into bowls, top with the shrimp and sauce, and finish with chopped parsley. Add Parmesan if you like a savory edge.
A final squeeze of lemon wakes everything up.