Make sure your butter, sour cream, and water are very cold.
In a large mixing bowl combine the flour, baking powder, sugar, salt, and garlic powder. Whisk to combine.
2 cups all purpose flour, 1 Tablespoon baking powder, 1 Tablespoon granulated sugar, ¼ teaspoon fine grind sea salt or kosher salt, ¼ teaspoon garlic powder
Cut the butter into small cubes about ½" in size and add to the flour mixture. Toss the butter in the flour to coat the cubes. Using a pastry blender (cutter) or a fork, break up the butter into smaller pieces as it combines with the flour. This is called cutting in the butter. When done, the mixture should have a lot of small pebbles or pea size pieces of butter and flour.
6 Tablespoons Butter
Add the grated cheddar cheese and the diced jalapeno pepper to the flour/butter mixture and toss to combine.
4 ounces sharp cheddar cheese, 1 medium jalapeño pepper
Make a well in the center of the flour and add the sour cream to the well. Using a fork or small spatula incorporate the sour cream into the flour mixture. You will end up with a very crumbly mixture that has larger pieces of "dough" in it.
½ cup sour cream
Add 4 Tablespoons (¼ cup) of very cold water to the mixture and toss to combine. The mixture will still look very dry and crumbly. Put the bowl in the refrigerator for 10 minutes. *Do not add more water at this time.
4-5 Tablespoons cold water
Forming and Cutting the Biscuit Dough
Preheat the oven to 450℉/230℃.
Remove the bowl with the biscuit mixture from the refrigerator and dump it onto a pastry mat or a clean large work surface. A clean countertop works great. It will be VERY crumbly, but don't add any extra water.
Press the crumbly mixture together until it starts to hold together. I use a folding technique where I press the dough down and then fold it back towards me while gathering the loose flour and incorporating it into the dough. You can add a little more water if needed but the dough can become sticky quick so only use 1 teaspoon at a time. After about 4-5 folds and turns of the dough it should hold together, but not be sticky.
Using your hands or a rolling pin, press or roll the dough to the thickness you want for your biscuits. Anywhere from ½" to 1" is good for the dough. They will double in height when baked. See recipe notes.
Use a 2½-3" biscuit cutter and press it straight down into the dough and pull it straight up. Don't twist or you can seal the edges and inhibit the rise of the biscuits. You can use a glass, but it may also compress the edges of the biscuit. Cut as many biscuits as you can from the rolled dough and then remove the biscuits and set them on a baking tray about 1-2" apart. I don't recommend lining the tray with parchment paper, I found this created a heat barrier and impeded the rise of the biscuits.
Bring the dough back together with your hands and roll it out again. Cut as many biscuits as you can. Repeat until all the dough has been used. Pinch off small quarter size round balls from the leftover scraps and place those on the tray for a few snack size biscuit bites.
Baking the Biscuits
Place the tray of biscuits into the preheated oven on the center rack. Lower the oven temperature to 425℉/220℃ and bake the biscuits for 13-15 minutes or until they are golden brown. You will see the shreds of cheese get darker than the biscuit. Remove the tray from the oven and immediately remove the biscuits from the tray and place them on a cooling rack. This is important because if they cool on the tray, the cheese tends to make the biscuits stick.
Seasoned Butter Topping
Mix together the seasonings in a small bowl.
1 teaspoon onion powder, ½ teaspoon garlic powder, ½ teaspoon powdered buttermilk, ¼ teaspoon fine grind sea salt or kosher salt, ¼ teaspoon dried parsley
Melt 4 Tablespoons of butter and mix the seasoning blend into the butter. Brush over the warm biscuits. Serve & Enjoy!