Prep: Preheat oven to 400°F and line a baking sheet with parchment paper.
Make the Biscuits: In a large bowl, whisk together the gluten-free flour, baking powder, salt, and sugar. Then, add the cold butter cubes and toss in the flour. Using your hands, two knives, or a bench scraper, break up the butter and incorporate it into the flour until it is coarse, with varying-sized pieces of butter. There should still be lots of pea-sized pieces. Next, pour in the cold buttermilk and mix until the dough is shaggy and has some dry and wet pieces.
Laminate the Dough: Dump the dough out onto a lightly floured surface. It will be very shaggy with some dry bits. Try to incorporate all of the dry bits and press everything together to create a square. It can be sloppy. Then, cut it in half and pile the halves on top of each other and press back down to create a square. Repeat once or twice more until the dry bits are much more incorporated and it is more dough-like.
Cut the Biscuits: Gently press or roll out the laminated dough until it is a 6x6-inch square. Cut into 9 squares with a sharp knife, but I prefer a bench scraper.
Bake or Air Fry: Add the lined baking sheet and brush the tops with buttermilk, and sprinkle with coarse sugar. Bake for 25 - 30 minutes or until risen and golden brown. You can also air fry the biscuits for 10 minutes at 400°F.
Strawberry Filling: In a large mixing bowl, add 1 cup of strawberry slices and honey. Mash them up with the back of a fork as best as you can. Then, add the remaining 4 cups strawberry slices and toss to combine. Let sit while biscuits bake or overnight in the refrigerator.
Whipped Cream: Whip ¾ cup heavy cream with an electric hand mixer or in a stand mixer with the whisk attachment until soft peaks form (about 2 - 3 minutes). You can do it by hand with a whisk, but it will take longer. Add the powdered sugar and vanilla and lightly whisk to incorporate. Assemble: Pull apart warm biscuits and layer with strawberries and whipped cream. Serve immediately and enjoy!