Heat the oil and butter in a skillet on a medium high heat.
Once hot, add the sliced onion and a pinch of salt and pepper.
Cook until soft, but not browned.
Add in the minced garlic, cook for a minute.
Push the onions and garlic to one side of the skillet and place the sliced zucchini flat in the skillet to cook. Sprinkle over some salt, pepper and the garlic powder.
Cook for about 3 to 4 minutes until the zucchini starts to brown.
Turn each piece of zucchini over and cook for another minute or two.
Mix the zucchini and onions together and serve with a sprinkle of black pepper and fresh parsley if desired.