Finely chop parsley and garlic by hand on a cutting board.
Add to a mixing bowl with oregano, chili flakes, salt, and black pepper.
Stir in red wine vinegar until everything is combined.
Slowly pour in olive oil while mixing. Add lemon juice if using.
Taste and adjust — more salt, vinegar, or chili flakes as needed.
Transfer to a glass jar. Rest for 15–30 minutes before using.
Spread 3–4 tablespoons on pizza dough as your base sauce. Add toppings and bake as usual.
Drizzle a little fresh chimichurri on top right after baking for extra brightness.