Heat oil in a 4-quart saucepan or stockpot over medium-high heat. Add onion and cook until translucent, about 6-7 minutes. Add garlic and cook an additional minute. Add carrots zucchini and squash and cook, stirring, until carrots begin to soften, 3-4 minutes. Add tomatoes, corn, vegetable broth, salt, pepper and basil and bring to a boil, skimming any foam off the top. Reduce hear and simmer for 15 minutes. Season with salt and pepper and remove from heat. Serve immediately, or pour into a thermos to take on the go.For the croutons:
Preheat oven to 350°F. Using a pastry brush, brush toasts on one side with olive oil and rub with garlic cloves. Arrange toasts on a cookie sheet and sprinkle evenly with cheese. Bake until toasts are browned and cheese bubbles, 10-12 minutes. Remove from heat and let cool.