Step 1

Heat 3 Tbsp. oil in a large saucepan over medium. Add onion and season with salt. Cook, stirring occasionally, until onion is beginning to soften, about 5 minutes. Add garlic and cook, stirring occasionally, until onion and garlic are very tender and just beginning to brown around the edges, about 5 minutes. Add rosemary and red pepper flakes and cook, stirring, until fragrant, about 30 seconds. Add chickpeas and tomatoes and cook, stirring occasionally, until tomatoes are slightly thickened, 6–8 minutes.

Step 2

Add pasta and 4 cups water to saucepan. Increase heat to medium-high, bring to a simmer, and cook, stirring occasionally to prevent pasta from sticking, until pasta is al dente, 13–16 minutes, depending on shape. Stir in parsley and 3 Tbsp. Parmesan; season with salt. Pluck out and discard rosemary sprig.

Step 3

Ladle pasta and broth into bowls. Drizzle with more oil, season with lots of black pepper, and top with more Parmesan.