This veggie and spicy onion relish makes the perfect sweet and zesty combo to top off your beef frankfurter. For the relish: Finely chop 5 small cucumbers, 3 red onions, 1 chili pepper and 2 green tomatoes. Add 2 tablespoons coarse salt and let sit overnight. When ready to use, rinse and drain. Heat 1 1/2 tablespoons vinegar in a saucepan, then add the relish and 1 cup sugar. Cook for 45 minutes on low heat, then add 1/2 teaspoon mustard and 1/2 teaspoon celery seeds to finish.