01 -  Preheat oven to 425°F. Line a baking sheet with parchment paper. 
 02 -  Combine whole milk and apple cider vinegar in a small bowl. Let stand for 5 minutes to curdle and create homemade buttermilk. 
 03 -  In a large mixing bowl, whisk together all-purpose flour, baking powder, baking soda, salt, and granulated sugar. 
 04 -  Add cold cubed unsalted butter to the dry mixture. Cut in using a pastry cutter or fork, until mixture forms coarse crumbs. 
 05 -  Stir shredded cheddar cheese and diced jalapeños into the flour and butter mixture. 
 06 -  Pour in chilled sweet tea and homemade buttermilk. Gently fold until a soft, slightly sticky dough forms; do not overmix. 
 07 -  Using a cookie scoop or clean hands, portion dough into 1 1/2-inch balls and arrange evenly on the prepared baking sheet. 
 08 -  Transfer to oven and bake for 13 to 15 minutes, until biscuit balls are golden brown. 
 09 -  Brush immediately with melted butter, and sprinkle with flaky sea salt if desired. 
 10 -  Enjoy warm, fresh from the oven.