Start by dicing the onions. In a cast iron skillet or stainless steel pan on medium heat, melt the butter. Add the onions and a good pinch of salt. Let cook, stirring to make sure nothing burns. Once the onions begin to sweat you can slightly turn the heat down. Add splashes of water as needed to pick up the brown bits and to keep the onion from burning. The whole process will take about 30-40 minutes. Stir in the Worchesteshire sauce at the end.
Blend the cottage cheese and greek yogurt with the garlic powder. Spoon into a bowl and stir in the mayo with. Stir through the onions once they are done and slightly cooled. Adjust salt and pepper as needed. Let set in the fridge before serving. Serve with your favorite potato chips or crackers