Fold about 1 teaspoon Southeast Asia sauce into your softened butter, making a delicious compound butter for topping your cornbread. Set aside. Preheat the oven to 400 degrees and place a 9-inch cast iron skillet, or baking dish, in the oven to preheat. In a large bowl, whisk together almost all of the melted butter (leaving about 1 Tablespoon for greasing your skillet), ¼ cup Southeast Asia sauce, buttermilk and Greek yogurt. Whisk in the eggs until well combined. Using a rubber spatula, fold in the cornmeal, flour, brown sugar, baking powder, baking soda and salt. Grease your preheated skillet with the reserved melted butter and pour the batter into the hot pan. Transfer to the oven and bake until the top is golden brown and a toothpick inserted into the center comes out clean, about 20-25 minutes. Let cool slightly, then spread with your Southeast Asia compound butter. Slice and serve.