Toast in the oven 6–8 minutes, flipping once halfway, until golden and crisp. If you prefer, broil 1–2 minutes per side watching carefully to avoid burning.

Optional: Rub the warm toasts with the cut side of the halved garlic clove for a subtle garlic flavor. Keep warm while preparing the shrimp.

Shrimp and sauce

Prepare shrimp

Pat the shrimp dry with paper towels to ensure good browning. Season both sides with 3/4 teaspoon kosher salt and 1/4 teaspoon black pepper (reserve the remainder for finishing).

Heat pan

Place a large (10–12 inch) skillet over medium-high heat. Add 1 tablespoon olive oil and 2 tablespoons butter. Allow the butter to melt and foam but not brown.

Sauté garlic

Add the sliced/minced garlic to the hot butter-oil mixture. Sauté, stirring constantly, about 30–45 seconds until fragrant and just beginning to turn golden (do not burn).

Cook shrimp

Add the shrimp to the skillet in a single layer. Cook 1.5–2 minutes without moving to get a sear, then flip and cook another 1–2 minutes until shrimp are opaque and just cooked through. If using larger shrimp, adjust time slightly. Remove shrimp to a plate and tent loosely with foil to keep warm.

Make sauce

Reduce heat to medium. Add the remaining 2 tablespoons butter to the pan. Carefully pour in the white wine (if using) and scrape up any browned bits from the bottom with a wooden spoon. Let the wine reduce for about 1 minute.

Finish sauce

Stir in lemon juice, smoked paprika, red pepper flakes, remaining 1/4 teaspoon salt and 1/4 teaspoon black pepper. Simmer gently 30 seconds to blend flavors.

Combine

Return the cooked shrimp to the skillet and toss to coat in the garlic-lemon butter sauce for 30–45 seconds to reheat the shrimp and marry flavors. Taste and adjust seasoning with more salt, lemon, or red pepper flakes if desired.

Garnish and serve

Sprinkle chopped parsley over the shrimp. Spoon the garlic-lemon butter and some of the pan sauce over the crostini or serve crostini on the side for dipping. Serve immediately.