Preheat oven to 400 F.
Make the sage brown butter by melting the butter over low heat in a small saucepan and adding 2 tbsp of the sage. Cook gently (should lightly bubble) until the sage is very fragrant and the milk solids in the butter turn light brown. When its finished, it will look like there is brown sand floating in the bottom of the pan and it will smell heavenly when its finished. Hang onto the butter wrapper to store the finished butter for later use.
Remove the pan from the heat and allow to cool to room temperature. Pour the contents of the pan into a food processor or blender and whir until the sage is completely blended into the melted butter. Return the mixture to the pan and set it in the freezer for about 3-4 minutes until it begins to set.
Remove the pan from the freezer and use a rubber spatula to scrape the hardening butter from the pan. Refreeze and repeat, thoroughly mixing and incorporating the hardened butter into itself to get a consistent texture and to keep the butter from freezing into a pan-shaped solid disc.
Once the butter is fully re-solidified, put it back in its original wrapper or some plastic wrap and reshape into a log. Sit it in the freezer until you are ready to add it to your biscuits!
In a large bowl, incorporate the dry ingredients (flour, baking powder and soda, salt, and the other 2 tbsp sage). Use a fork or whisk to thoroughly incorporate them.
Before moving further, pour out the half and half or milk into a measuring cup or glass and add the lemon juice or vinegar. Mix thoroughly and let rest 5-10 minutes until it becomes bubbly. Youve essentially created buttermilk.
Remove your cold sage butter from the fridge or freezer and cut into approx. half-inch cubes. Break apart the cubes and lightly toss them into the flour mixture. Using your hands, smash each cube into a flat disc and break it up into small bits about the size of a dime, lightly tossing the butter bits into the flour as you go.
Once the butter is broken up and integrated into the flour, add the buttermilk a little at a time and toss with your hands until a shaggy dough forms. It is ok if it has cracks and visible flour on it. This is ideal. Roughly shape it into a 1 tall square or rectangle. Throw it in the freezer for a few minutes to re-cool the dough.
Remove the dough from the freezer and cut into four equal parts. Stack the parts into a small tower and smash them back down into a flat rectangle similar to the original shape. Refreeze the dough for another ten minutes. Repeat this step 1-2 times. The more you do it the more flaky layers our biscuits will have!
Roll or press the dough back out into its 1 rectangle for cutting the final biscuits. Use a knife to cut it into large squares and place on a lightly greased baking rack or sheet. This should yield about six 3 c 3 biscuits. Coat each biscuit with about 1/2 tsp (+/-) egg wash and bake at 400 F for 17-20 minutes.
When the biscuits have five (5) mins. left, open the oven and add another layer of egg wash.
Once the biscuits are done, they should have a deep, golden, shiny crust on top. Enjoy with butter, your favorite jam, or as a breakfast sandwich.
