In a large, deep skillet or pan, melt the butter over medium heat.
Add the minced garlic and sauté for about 1 minute until fragrant, being careful not to burn it.
Stir in the vegetable broth and bring it to a gentle boil.
Once boiling, add the spaghetti or fettuccine to the pan. Ensure the pasta is submerged in the broth.
Reduce the heat to medium-low, cover, and let the pasta cook for about 10-12 minutes, stirring occasionally, until al dente and most of the broth has been absorbed.
Stir in the heavy cream, onion powder, and red pepper flakes. Cook for an additional 2-3 minutes to thicken the sauce slightly.
Remove the pan from heat and mix in the Parmesan cheese, stirring until melted and creamy.
Season with salt and pepper to taste. If desired, sprinkle the lemon zest for added brightness and flavor.
Garnish with fresh chopped parsley before serving.
Notes
Serve in a large bowl or plate, topping each serving with a sprinkle of extra Parmesan and a few parsley leaves for color. A light drizzle of olive oil can also add a nice shimmer!