Chicken Pesto Pasta (Quick Pantry Dinner)

2 Bring large pot of water to a boil. Salt the water generously (about 1 tablespoon kosher salt or 2 teaspoons table salt per quart). Add the pasta and cook until al dente. Reserve about ½ cup of the cooking water before draining the pasta.
0 While the pasta cooks, heat the olive oil in a large skillet over medium-high heat. Add the chicken and ½ teaspoon salt. Cook until it’s cooked through no longer pink, 5-7 minutes, stirring occasionally.
1 Add the garlic and red pepper to the pan, cooking just until the garlic smells good, about 30 seconds. Stir in the pesto and ¼ cup of the pasta water. 
3 Adjust the heat to low and add the cooked pasta and cheese to the pan, stirring to combine. If the sauce looks too thick, drizzle in a bit more pasta water to reach your desired consistency.
4 Transfer the pasta to a serving bowl. Serve hot, with the nuts sprinkled over, and additional grated cheese alongside.