Cook the Pasta: In a large pot of salted boiling water, cook the pasta according to package directions until al dente. Reserve about 1 cup of the pasta water, then drain and set aside.
Sauté Turkey: In a large skillet over medium heat, melt 0.25 cup of butter. Add the chopped onion and garlic, and sauté for about 2-3 minutes until fragrant. Add the ground turkey, season with salt, pepper, and dried oregano. Cook until the turkey is browned and cooked through, about 5-7 minutes.
Add Vegetables: Stir in the cherry tomatoes and cook for another 2-3 minutes until they soften. Add the spinach leaves and cook until wilted, about 1 minute.
Combine Pasta and Turkey Mixture: Lower the heat and mix the cooked pasta into the skillet with the turkey and veggie mix. If the mixture appears dry, add some of the reserved pasta water—start with 0.25 cup and adjust as necessary.
Herb Butter Finish: Remove the skillet from heat. Stir in the remaining 0.25 cup of butter, fresh parsley, basil, lemon zest, and lemon juice. Toss everything together until well combined and creamy.
Serve: Plate the pasta and sprinkle with grated Parmesan cheese. Garnish with extra herbs if desired.