Peel and slice the onions into thin rings. Wash and slice the tomato.

Heat a pan over medium heat, add some oil and the sliced onions. Immediately add 2 tablespoons of sugar and a little salt. For a sweeter result, you can add more sugar. Fry over low heat for 10–12 minutes, until the onions are caramelized. Then add the balsamic vinegar and simmer for a few more minutes until the onions become sticky.

Prepare the sauce: Mix together BBQ sauce, mayonnaise, and mustard.

Rinse the arugula under cold water in a sieve and let it drain.

Heat a drop of oil in the same pan over medium heat. Add the burger patties and cook for about 4 minutes on each side. Spread goat cheese over the hot patties so the cheese melts slightly. Toast the burger buns on both sides until golden.

Assemble the burger: Spread the sauce on the bottom bun, then add tomato slices, the burger patty with goat cheese, caramelized onions, arugula, and finally the top bun. Enjoy!