Grill the corn on all sides until nicely charred and tender. Lather with butter.
Grill the onion and peppers until tender and nicely charred. Then dice.
Grill the sausage, getting a nice char on all sides to an internal temperature of 155°F (68°C) using a thermometer.
Mix the ingredients together for the sparkling lemon water.
Place the cooked sausage link on the bun, and top with peppers and onions. Top with ketchup or mustard as preferred. Enjoy with grilled corn and lemon sparkling water.