Preheat the oven to 400 degrees F.
Heat the oil in a small skillet over medium heat. Add the onions and cook until tender, about 7 minutes.
In a large bowl, add the milk and egg to the biscuit mix, stirring just until the mix is moistened. Fold in the onions and 1/2 cup of the cheese.
Spoon the dough into a greased 8-inch round cake pan. Mix the onion salt into the melted butter and drizzle the mixture over the dough. Sprinkle the bread with chives or parsley and bake for 15 minutes. Top the bread with the remaining 1/2 cup cheese and bake until the bread is cooked through and the cheese top golden, about 5 minutes longer, Cut the bread into wedges and serve warm with butter.