Begin by dicing cold unsalted butter into 1/4" cubes and placing them in the freezer while you prepare the dry ingredients.

In a large bowl or a stand mixer, combine flour, sugar, baking powder, baking soda, kosher salt, black pepper, minced sage, and grated Gruyere cheese. Stir until well combined.

Remove the chilled butter from the freezer and add it to the flour mixture. Use a pastry cutter or your fingers to mix until the mixture resembles clumpy sand.

Slowly stream in cold buttermilk and heavy cream into the flour mixture. Gently mix until the dough just begins to come together.

Transfer the dough to a lightly floured surface and roll it out into an 8"x11" rectangle. Fold the dough into thirds, like a letter, then roll it out again to the same size. Repeat this process three more times.

Cut the dough into 9 squares and arrange them on a baking sheet lined with parchment paper. Refrigerate for 45 minutes.

Preheat your oven to 450°F.

Brush the tops with heavy cream and sprinkle a pinch of flaky sea salt over each one. Bake for 18-20 minutes, or until they are puffed up and golden brown.