Pound Chicken: Lay a chicken breast on your chopping board, cover with cling film and pinch around the edges (so no juices escape). Pound until even thickness, but not so thin it starts breaking apart. Around 3/4" is fine. Cut and discard any parts around the breast that rip off (can cut the tails off to create circle/burger shape if you want). Repeat with remaining breasts.
Marinate: In a large mixing bowl combine buttermilk, hot sauce, salt and white pepper. Add in the chicken breasts and combine to ensure they'll all coated. Cover with cling film and marinate in the fridge. I recommend a minimum of 4 hours (up to overnight) but just as long as you have time for. Take the chicken out the fridge 30mins before needed to bring close to room temp (see notes).
Dredge: In a large shallow dish or tray combine flour with paprika, cayenne pepper, onion & garlic powder, baking powder and salt & black pepper. One by one coat the breasts in the flour, making sure you completely coat each time. Really get in all the cracks and crevices of the chicken to create lots of little flaky parts. Place to one side.
Fry: In a large pot or deep pan heat up oil to 180C/356F. In batches of 1-2 (depending on pot size), carefully lower the chicken in the hot oil. The temp will likely drop to around 165C/300F, just maintain that heat as the chicken fries. Depending on the thickness of the chicken it'll take around 4-5mins on one side, then flip and continue frying for another couple of minutes. The chicken should be deep golden, visibly crunchy with the bubbling oil starting to slow down. The internal temp of the chicken should reach 75C/165F. Carefully remove and rest on wire rack with paper towels underneath (don't place directly on paper towel or they'll lose crispiness). Bring oil temp back up to 180C/356F between each batch.
Glaze: Once you've fried the 4 breasts, scoop out 1/2cup of the oil and pour into a mixing bowl. Add in honey, hot sauce, smoked paprika, garlic powder, salt & black pepper and whisk until it emulsifies and thickens into a glaze. Brush both sides of the chicken with the glaze.
Sandwich: Stack the sandwich in the following order - toasted bun, mayonnaise, lettuce, chicken, pickles & jalapeños, top bun. Enjoy!