In a Dutch oven, heat the oil over medium heat. Add the carrots and onion; cook and stir until crisp-tender, 6 to 8 minutes. Add the garlic; cook and stir one minute longer. Stir in the flour until blended; add the white wine. Increase the heat to medium-high and cook, stirring occasionally, until the wine is reduced by half, 2 to 3 minutes. Gradually whisk in the broth. Bring to a boil, stirring constantly; cook and stir until slightly thickened, 3 to 5 minutes.
Add the tortellini, Italian seasoning, salt and pepper (and crushed red pepper, if using). Reduce the heat and simmer, uncovered, just until the tortellini are tender, 3 to 5 minutes.
Stir in the cream and spinach; cook and stir just until the spinach is wilted, 1 to 2 minutes longer. Serve topped with Parmesan cheese.