Tuna salad with hard-boiled egg is a perennial favorite, and tuna melts are always a lunchtime treatso why not combine the two? A somewhat traditional tuna salad is mixed with cheddar cheese, nestled in a hot dog roll, and then warmed in the oven until hot and gooey. This recipe even takes it up a notch by adding sliced pimento-stuffed olives, imparting an unexpected but delicious flavor while adding a bit of color. These are great sandwiches for a party. Bake them and then keep them wrapped and warm for serving in the slow cooker on the warm or low setting.