Tomato Florentine Soup

Name: Tomato Florentine Soup
Total time: 45 min
Yield: 4 servings
Ingredients: 2 tablespoons unsalted butter; 43 1/2 ounces diced tomatoes fire-roasted, drained and juice reserved; 1 onion medium, chopped fine; 1 tablespoon tomato paste; 1 tablespoon brown sugar packed; 1 pinch red pepper flakes; 2 tablespoons flour all-purpose; 3 garlic cloves minced; 5 cups low sodium chicken broth or vegetable broth; 4 ounces macaroni small, ditalini, or tubettini; 10 ounces baby spinach fresh; kosher salt; freshly ground black pepper