Prep Ingredients: Pat the shrimp thoroughly dry with paper towels and place them in a medium bowl. Zest the entire lemon over the shrimp, then cut the zested lemon in half and set aside for later.
Sear the Shrimp: Heat the avocado oil in a large skillet or Dutch oven over high heat until it shimmers. Arrange the shrimp in a single layer and sear for 60-90 seconds per side, just until they turn pink and develop a slight crust. Do not cook them all the way through. Use a slotted spoon to transfer the seared shrimp to a clean plate.
Sauté Aromatics: Reduce the heat to medium. Add the sliced shallots to the skillet and cook, stirring frequently, until they soften, about 3-4 minutes. Stir in the minced garlic and smoked paprika, and cook for another minute until fragrant.
Wilt the Spinach: Pour in the white wine to deglaze the pan, scraping up any flavorful browned bits from the bottom. Add the spinach in large handfuls, sprinkling the salt-free lemon pepper seasoning on top. Stir continuously until all the spinach has wilted down, about 4-6 minutes.
Create the Sauce: Reduce the heat to low. Squeeze the juice from both reserved lemon halves into the spinach. Stir in the extra-virgin olive oil, black pepper, and cayenne pepper until a cohesive sauce forms.
Finish the Dish: Return the seared shrimp and any accumulated juices to the skillet. Gently fold everything together and cook for 2-3 minutes, allowing the shrimp to warm through and finish cooking.
Serve: To serve, create a bed of the garlicky spinach on each plate and arrange the shrimp on top. Drizzle with any remaining pan sauce and garnish generously with fresh dill.