Season the ground meat with pepper and salt and shape into 4 burgers. Pan-fry or grill the burgers until they are just done and grill the insides of the buns. Preheat the oven to 220°C (428°F), cut the sweet potatoes into French fries of 0.5 cm thickness and mix in a bowl with some sunflower oil, pepper and spices to taste (paprika powder, garlic powder, cumin, etc.). Roast in the oven for about 20-30 min, turning over after 10 min and again after 20 min. Keep an eye on how they are cooking, taking care that they don’t turn too brown. Take them out of the oven, then sprinkle with salt and a squeeze of lemon juice. 

Assemble the burgers: bun/baby spinach (drizzled with a bit of olive oil)/pickles/slices of avocado/ burger/mayonnaise and chutney and freshly grated parmesan to finish. Serve with the fries and a salad to taste. A treat for your taste buds!

Red onion chutney:
Cut 4 red onions and 1 red chili into thin slices. Put it all into a saucepan with some olive oil on medium heat and stir-fry for 10 minutes. Add 50 g of brown sugar, a tablespoon of honey, a bay leaf, a teaspoon of thyme leaves, a finely chopped clove of garlic, 75 ml of balsamic vinegar and 75 ml of red wine vinegar. Simmer for 15 minutes so the liquid evaporates and the onions get soft and sticky. Remove the bay leaf, season with pepper and salt, and allow to cool.