1. For the marinade, combine the ingredients in a zippered plastic bag. Add the squab, and refrigerate for at least 8 hours.

2. Remove the squab from the marinade and reserve. Season the squab with salt and pepper. Heat 1 tbsp of the oil in a large frying pan over medium heat. Add the bacon and cook, stirring, about 5 minutes, until golden. Stir in the shallots and cook for 2 minutes more. Transfer to a plate and tent with aluminum foil.

3. Melt the butter over medium-high heat. Add the squab and cook, turning once, for 5 minutes, or until golden on both sides. Meanwhile, brush the bread slices with the remaining oil and toast until golden. Spread with the mustard.

4. Transfer the squab to the plate and tent with foil. Pour the reserved marinade into the pan, bring to a boil, and cook about 5 minutes, or until reduced by half.

5. Cut each squab breast in half diagonally Divide the mâche among 4 dinner plates. Top each salad with a slice of toasted bread, 4 breast portions, and the lardon and shallot mixture. Drizzle with the reduced marinade and serve at once.