Peel and finely dice the onion and knead it with the mince in a bowl. Season with pepper and form 4 meatballs with moistened hands. Heat the oil in a pan and leave the bacon in it until crispy.
Remove the bacon from the pan and place it on kitchen paper. Fry the meatballs in the hot bacon fat while turning for about 10 minutes.
Covered deep-frozen beans and cook in little boiling salted water according to the package instructions. Drain the beans and let them drain.
For the mashed potatoes, boil 500 ml of water and a level teaspoon of salt. Remove the pot from the heat and add cold milk. Stir in the puree powder with a whisk. After approx. 1 minute turn the sauce again.
Crumble the bacon and, except for something to garnish, fold into the purée.
Melt the fat in the pot, toss the beans and parsley in the butter. Serve the beans with the meatballs and the bacon and mashed potatoes. Garnish the puree with the remaining bacon.