Take a large bowl and add the minced meat and salt to the bowl.

Mix the meat thoroughly with the salt using the dough hooks of a hand mixer.

Peel the onion and grate it coarsely.

Stir onion, eggs, oat flakes, grated lemon zest, and chopped parsley into the meat. Add milk until the mixture has a suitable consistency.

Preferably, let the mixture rest in the fridge for about 1 hour (although you can use the mixture immediately, it benefits from resting).

Heat a large pan with butter and oil. Brown the meatballs on both sides over high heat until they form a crust. Avoid placing too many meatballs in the pan at once, as the temperature will drop too much, causing the meat to boil instead of frying.

Cook the meatballs over medium heat until they are cooked through - the cooking time depends on the size of the meatballs, try cutting one in half to check if it's done.

Remove the meatballs from the pan. If needed, place them in an ovenproof dish and keep them warm in the oven at 120 degrees Celsius (248 degrees Fahrenheit) while you make the sauce.

Pour vegetable bouillon into the pan where you cooked the meatballs, and bring the liquid to a boil.

Add cream and, if necessary, thicken the sauce with a little cornstarch dissolved in water.

Season the sauce with salt, pepper, vinegar, and a little sugar, until it has the right consistency.

Serve the meatballs with boiled potatoes sprinkled with parsley, brown sauce, and for example steamed cauliflower or broccoli.