Lightly grease a tube pan lightly with oil and preheat the oven to 350℉.
In a large bowl, whisk together the 3 cups gluten free flour, 1 cup almond flour, 1 ½ cups sugar, 3 teaspoons baking powder, and ½ teaspoon fine sea salt.
Whisk in the 4 large eggs, 1 cup oil, ⅓ cup apple juice, and 2 teaspoons pure vanilla extract, then use a spoon to make sure the batter is smooth and the dry ingredients are well incorporated. Let the batter rest while you prepare the pears.
Peel and core the 2 pears, then cut the pieces into ¼-inch chunks. Mix the pears with the 2 teaspoons ground cinnamon and 3 tablespoons brown sugar.
Then, spread half of the batter in the tube pan and sprinkle half of the pear mixture evenly across it. Add the rest of the batter and top with the remaining pears. Rest the batter for about 15 minutes.
Place pan in the oven and bake for 1 hour 15 minutes-1 hour 30 minutes, checking frequently, until a tester inserted comes out clean, the top is slightly firm when gently pressed, and the edges are starting to come away from the pan.
Remove from oven and cool in pan for 25 minutes on a wire rack, then turn out onto a rack to cool completely.
Notes
NOTE: The original version of this recipe called for 1 ¾ cups of almond flour + 1 ¼ cups of sorghum flour + ½ cup of tapioca flour for the flour portion. This is also delicious!
Remove from the pan gently. The cake will be a bit delicate even after cooling, so be careful when you remove it from the pan. Be very gentle when removing the bottom layer of the tube pan and have the rack ready so that you can transfer it there to finish cooling to room temperature.
Place on a baking sheet. When using a tube pan, batter can sometimes leak out the bottom. To prevent spilling and burning on the floor of the oven, place the pan on a baking sheet to catch any extra batter.
Prep the batter in order of ingredients. The reason this recipe works as a one-bowl method is that the batter is prepped following the order in the ingredient list. This helps everything meld together into a smooth batter.
Use another pan. If you don't have a tube pan, a large cake pan, such as a 10-inch springform cake pan, works well.
To serve: Freshly whipped cream or vanilla ice cream, and don't forget the coffee!