Gather all the ingredients and slice/chop the herb, vegetables, and the sausage.
Bring a pot of water to a boil over medium-high heat, salt the water, add the pasta and a splash of oil and cook according to the package instruction minus about 10 percent less than the required time, you will continue the cooking in the sauce. Reserve about a quarter cup of water from the pasta.
While the pasta is cooking, place a skillet over medium-high heat, heat up about a teaspoon of oil then brown the sliced chicken sausage (feel free to use any sausage of your choice) about 2 minutes, then transfer into a plate.
Heat up the remaining oil in the same skillet, add the chopped onions, carrot, and garlic cook until the carrot is a little bit soft, stir in the tomatoes, red pepper flakes (if you’re using), parsley, and combine. Cook for about 1 minute, continue to stir to avoid burning. Season with salt and pepper.
Add the sausage, and let it absorb the flavor.
Add the cooked pasta and combine. Cook until the pasta, about 1/4 cup of pasta water (or less), cook to your desired texture. Check the seasoning and readjust if necessary.
Serve and enjoy!
Sausage and pasta with boiled egg garnished with scallion.