Scallops with tarragon

8 scallops 1 lemon, zest of 1 dash safflower oil 1 shallots or 1 onion , finely chopped 1 lb very ripe tomatoes , quartered or 1 (14 ounce) can whole tomatoes[...]

2 lbs yukon gold potatoes , peeled, cut into 1-inch pieces 1 teaspoon salt 1/2 cup butter (1 stick) 1 tablespoon butter , room temperature 2/3 cup whole milk[...]