Boil a large pot of water with 2 tablespoons of salt. Add 4 quarts of water and prepare to cook spaghetti.

Cook the spaghetti in boiling water for about 8-10 minutes until al dente. Reserve 1 cup of pasta water before draining.

Heat a skillet over medium heat, add 2 tablespoons of olive oil, then add minced garlic and red pepper flakes. Sauté for 1-2 minutes.

Add drained spaghetti to the skillet and pour in ½ cup reserved pasta water. Toss to combine.

Add chopped parsley and grated Parmesan to the spaghetti. Season with salt and black pepper to taste.

In a bowl, mix ½ cup softened unsalted butter, minced garlic, remaining parsley, and garlic powder. Mix until smooth.

Slice the Italian bread lengthwise and spread garlic butter mixture generously on each side.

Preheat the oven to 375°F (190°C). Bake the bread halves cut-side up for 10-12 minutes.

Switch to broil mode and cook for an additional 1-2 minutes until crisp.

Slice the garlic bread and serve hot with spaghetti, garnishing with extra Parmesan and parsley.