Melt butter in large saucepan. Add garlic, zucchini, carrots, and onion. Saute until veggies are tender. Stir in broccoli and broth. Simmer until broccoli is tender. Meanwhile, melt butter in large pot. Whisk in flour and cook for a minute or two. Whisk in milk until smooth -- simmer until thickened. Whisk in cheddar cheese. Pour vegetable mixture into cheese sauce and whisk until smooth. Serve immediately.