Start by filling a medium-sized saucepan with water and bring it to a boil over high heat. Once it reaches a rolling boil, add a generous pinch of salt. This will enhance the flavor of your pasta significantly.
Next, add your chosen pasta to the boiling water. Cook according to the package instructions until it reaches an al dente texture. This typically takes around eight to ten minutes. Remember, you want it to be firm to the bite!
Three minutes before your pasta is done cooking, gently stir in the chopped broccolini. This will allow it to cook perfectly without becoming mushy. The broccolini should be vibrant green and tender yet still have a bit of crunch.
Once the pasta is perfectly cooked, reserve one cup of the starchy pasta water. This is crucial for creating a silky sauce later. Use your kitchen tongs to remove the broccolini from the saucepan and set it aside, then drain the pasta.
While the pasta is draining, heat a 12-inch stainless steel skillet over medium heat. Add two tablespoons of unsalted butter and let it melt, swirling the pan to coat the bottom evenly.
Now, add the sliced mushrooms into the skillet. Season them with salt and pepper. Sweat the mushrooms for about three to four minutes, allowing them to soften and release their natural juices. You want them to be golden and fragrant.
Remove the cooked mushrooms from the skillet and place them on a plate. In the same skillet, add the remaining two tablespoons of butter and minced garlic. Cook for about thirty seconds, just until the garlic becomes aromatic. Be careful not to burn it; burnt garlic can ruin the dish.
Add the drained pasta and a splash of the reserved pasta water into the skillet with the butter and garlic. Stir in the grated parmesan cheese, tossing everything together using your kitchen tongs. This is where the magic happens; the heat from the pasta will create a creamy sauce. Add more pasta water if necessary to achieve your desired consistency.
Finally, gently fold in the cooked mushrooms and broccolini into the pasta. Ensure everything is well combined. Sprinkle the dish with crushed red pepper flakes, enhancing the flavor with a little heat.
Serve immediately, and enjoy your homemade Broccolini Pasta while it's warm!