Cut the baguette in half crosswise and then halve each portion lengthwise. Spread the chipotle mayonnaise on the top of each baguette half.
On the bottom of each baguette half, layer the turkey, tomato, onions, avocado, and lettuce.
Place the top of the baguette on each sandwich and serve immediately.
Wrap and refrigerate the sandwiches up to 1 day ahead, but for the best texture, store the mayonnaise separately and add it right before serving.Nutritional values are approximate and based on 1 sandwich.