Cook Pasta : Bring a pot of salted water to a boil. Cook elbow macaroni according to package instructions until al dente. Drain and set aside.
Prepare Spinach Puree : In a blender or food processor, blend fresh spinach with 1/4 cup milk until smooth and vibrant green.
Make Cheese Sauce : In a medium saucepan, melt butter over medium heat. Whisk in flour and cook 1–2 minutes to form a roux. Gradually add milk, whisking constantly until thickened.
Add Spinach u0026 Cheese : Stir in spinach puree, shredded cheddar cheese, garlic powder, salt, and pepper. Continue stirring until cheese is melted and the sauce is smooth.
Combine with Pasta : Add cooked macaroni to the sauce and stir until pasta is fully coated in creamy green sauce.
Add Monster Eyes : Decorate with cherry tomatoes, sliced olives, or mozzarella balls to create fun monster eyes.
Serve : Transfer to a serving dish and serve immediately.