Peach, Bacon, Avocado Sandwich

For the Basil Sauce 1/4 cup packed basil 1 tsp lemon juice 3 Tbsp mayonnaise, homemade recommended Salt and pepper For the Sandwiches 4 pieces multi-grain bread, toasted 6-8 slices bacon, cooked 1 ripe peach, sliced 1 avocado, sliced Arugula