Bring a large pot of salted water to a boil and cook the pasta until just al dente, about 8 minutes. Drain and set aside, reserving a splash of pasta water.
While the pasta cooks, heat 2 tablespoons of olive oil in a large skillet over medium heat until shimmering and fragrant.
Add the minced garlic to the skillet and sauté for about 30 seconds until fragrant and slightly golden, stirring constantly to prevent burning.
Place the shrimp into the skillet and cook for 2-3 minutes per side until they turn pink and opaque, filling the kitchen with a sweet, briny aroma. Use a slotted spoon to remove and set aside.
Add a splash more olive oil if needed, then toss in the fresh spinach. Cook for 1-2 minutes, stirring until the greens wilt and turn bright green, releasing a fresh aroma.
Return the cooked shrimp to the skillet, then add the drained pasta. Toss gently to combine, allowing the flavors to meld for about a minute over low heat.
Squeeze the juice of the lemon over the mixture, then add the lemon zest and red pepper flakes. Toss again, adding a splash of reserved pasta water if the dish seems dry, to create a silky sauce coating all ingredients.
Taste the dish and adjust seasoning with more lemon juice, salt, or red pepper flakes as desired. Serve immediately, garnished with extra lemon zest or a drizzle of olive oil for a bright, fresh finish.
