In a medium size saucepan begin boiling 6 cups of water over high heat. When boiling add the Penne pasta and cook until al dente (I added my pasta to the water once the onions were translucent).
In a large nonstick skillet add the butter and the olive oil over medium heat. Once the butter has melted add in the diced onions and let cook for 5-6 minutes until translucent, stirring occasionally. Next, add in the garlic and stir until fragrant. Then add in the diced tomatoes and reduce the heat to medium low.
In a small bowl combine the salt, pepper, and garlic powder. Then sprinkle the seasoning mix onto both sides of each shrimp.
Once the tomatoes are broken down, and the pasta is almost ready, add the shrimp into the skillet with the tomatoes, onions, and garlic. Cook on both sides for about 2 minutes per side- depending on the size of your shrimp.
When the shrimp is fully white on the outside begin adding in the cooked Penne pasta. It's important not to drain the pasta but instead to use a pasta fork to scoop the pasta out of the water and directly into the skillet with the other ingredients. Mix the ingredients around until all is well combined. Turn off the heat.
Next, sprinkle in the Parmesan cheese in two batches. Be sure to stir the dish between cheese batches so that it is evenly distributed. Repeat this same process but with the spinach so that it can get evenly distributed. The spinach should begin to welt down in the pasta.
Serve with a light salad or some crusty french bread. But the most important step is to enjoy!