We always arrive at Vincent Market Bistro with the best of intentions. The Organic Vegetable Medley salad is a wonderful, seasonal mix of super-fresh veggies, tossed in a light vinaigrette — so tasty we forget we're eating so light. And if it were only that salad that passed our lips, we'd look like Heidi Klum. Alas, that evil Vincent Guerithault has other plans. Each and every lunch at his sweet little bistro begins with a plateful of fresh-baked croissants. Even if we are able to keep our paws off the bread, you can be guaranteed that, at meal's end, the waiter will arrive with dessert — maybe a lemon bar with housemade raspberry sorbet or some decadent chocolate thing. If you didn't actually order it, it doesn't have calories, right? That's what we'll keep telling ourselves, because amazingly, the croissants and the dessert are free; we can manage to get out of this ritzy place at lunchtime for just a bit over $10. Now if we could just get into our jeans.