Mix all the burger ingredients in a bowl. Let the mixture rest for 30 minutes on the counter top.
Spread the mixture on parchment paper. Add another parchment paper on top and press down lightly to create an even ½" thick layer. Remove the parchment paper and start shaping your burgers by using a ring mold or a wide glass to cut out perfect patties.
Heat up a panini press/grill/pan. Rub oil on the burgers and sear them for 2 to 3 minutes on each side, according to your desired cooking level.
Fried potato slices:
Peel a medium potato and cut it into ¼” thick slices.
Heat up a frying pan with ½" oil over medium-high heat and fry the slices until golden. Remove from the pan and let them cool off on a baking rack or a plate with paper towel.
Fried green chili pepper:
Cut a chili pepper in half (remove the seeds for reduced heat) and fry over medium-high heat for 2 to 3 minutes on each side.
Sautéed onion and mushrooms:
Fry the onion until golden, then add the mushrooms and fry until they start to soften.
Add in the parsley, date syrup, salt and black pepper and stir for a minute. Remove from the pan.