Cook the Tortellini: Bring a large pot of salted water to a boil. Add tortellini and cook according to package directions (usually 3–5 minutes for fresh tortellini) until al dente. Reserve ¼ cup of the pasta water, then drain and set aside.

Make the Spinach Pesto: In a food processor or blender, combine spinach, basil, Parmesan cheese, pine nuts, and garlic. Pulse until finely chopped. With the motor running, slowly drizzle in olive oil until smooth and creamy. Add lemon juice, salt, and pepper, then taste and adjust seasoning.

Prepare the Parmesan Crumbs: In a small skillet, melt butter over medium heat. Add panko breadcrumbs and toast, stirring often, until golden brown and crisp (about 3–4 minutes). Remove from heat and mix in Parmesan cheese, salt, and pepper. Set aside.

Combine Tortellini and Pesto: In a large pan, gently heat the spinach pesto over low heat. Add the cooked tortellini and toss to coat evenly, adding a splash of the reserved pasta water if needed for creaminess.

Serve: Divide the pesto-coated tortellini among serving plates. Sprinkle generously with Parmesan crumbs and garnish with fresh basil leaves and extra Parmesan.