Melt the butter or coconut oil in a saucepan over medium heat. Add the oats and toast for about 2 to 3 minutes, stirring often, until fragrant.
Turn the heat to low and carefully pour in the water, milk, apple, brown sugar, cinnamon, allspice, salt and vanilla extract, stirring.
Bring to a boil, then return heat to low and cook for 7 to 8 minutes until tender, then remove from the heat. Top with desired toppings and serve.
