Lemon, Ham and Arugula Pasta

Ingredients

• • 3/4 lb (340 g) penne or other short pasta
  • 1 1/2 cups (225 g) frozen green peas, thawed
  • 2 garlic cloves, finely chopped
  • 2 tbsp butter
  • 2 tbsp unbleached all-purpose flour
  • 1 1/2 cups (375 ml) chicken broth
  • 5 oz (140 g) white ham, diced large (see note)
  • 2 lemons, zest finely grated
  • 1/4 tsp red pepper flakes, or more to taste
  • 1 cup (70 g) fresh Parmesan cheese, finely grated, plus more for serving
  • 3 tbsp (45 ml) lemon juice
  • 2 cups (50 g) arugula, coarsely chopped