Preheat oven to 350°F and grease a 9-inch round cake pan or springform pan.
Toss sliced apples with melted butter and brown sugar, then arrange them in the bottom of the prepared pan in a circular pattern.
In a large bowl, whisk together oat flour, almond flour, sugar, ginger, cinnamon, cloves, baking soda, and salt.
In another bowl, combine molasses, milk, oil, and eggs, whisking until smooth.
Pour wet ingredients into dry ingredients and mix until just combined, then carefully pour batter over the arranged apples.
Bake for 40-45 minutes until a toothpick inserted in the center comes out clean, then cool for 10 minutes before inverting onto a serving plate.