Cook the bacon. Heat a skillet over medium heat. When hot, add bacon then cook, stirring occasionally, until crispy on all sides, about 5-7 minutes. Use a slotted spoon to transfer to a paper towel-lined bowl. Set aside.
Mix the dry ingredients. Whisk together 3¼ cups (390g) all-purpose flour, 2¼ tsp baking powder, ½ tsp baking soda, and 1½ tsp kosher salt in a large bowl.
Add butter. Use a pastry cutter or your hands to cut in 2 sticks (227g) of cold butter until pea-sized pieces form.
Flavor the dough. Add 1 cup (100g) shredded Cheddar, the crispy bacon, minced jalapeño, and 1 cup (237ml) cold buttermilk. Mix with a wooden spoon until just combined.
Roll out the dough. Pour the dough out onto a lightly floured surface and gently pat into a rectangle about 1½” tall. The dough should be craggly and just holding together. There will be bits of flour falling off on all sides. Use a bench scraper to cut the dough into 4 equal rectangles, then carefully stack them on top of each other. Press down slightly, then repeat once more, patting into a 1½” tall rectangle, cutting into four equal quadrants, and stacking them. Use a lightly floured rolling pin or your hands to gently roll out into a 1½” tall rectangle (the shape isn’t as important as keeping the height!).
Chill the biscuits. Use a bench scraper to cut the dough into 8 (large) or 9 (smaller) biscuits, then carefully transfer to a baking sheet lined with parchment paper, leaving about 2-inches between each. Transfer the biscuits to a freezer for 10-15 minutes (or a fridge, just let them chill a bit longer). Preheat an oven to 425°F (220°C).
Bake. Combine 3 Tbsp melted butter and 1 Tbsp honey in a small bowl, then brush on top of the biscuits. Sprinkle each with a bit of flaky sea salt, then bake for 15-20 minutes, or until the biscuits have puffed up and the tops are golden brown. Serve warm with butter, honey, and/or jam.