Melt the butter and olive oil in a fry pan over low-medium heat. Add the onion and fry gently for 8-10 minutes, or until softened. Add the garlic plus 1 teaspoon of Australian Bush Herbs.
Add the sourdough to a food processor and blitz it in short bursts to turn the bread into a mixture of coarse and finer chunks.
Add the breadcrumbs to a bowl along with the nuts, lemon zest, remaining 1½ teaspoons of Australian Bush Herbs, parsley, cooked onions, and beaten eggs. Season with salt and pepper to taste and mix well to combine.
Spoon the mixture into an oiled mini muffin tray, or simply roll into balls and place them on a baking sheet. Cook for 25 minutes or until golden brown. Let them cool slightly before removing them from the tray and serving them.
