In a large bowl, whisk together the flour, cornmeal, baking powder, baking soda, salt, garlic powder, and black pepper until evenly combined.
In a separate bowl, whisk the egg, buttermilk, and honey until smooth. Grate the onion on the large holes of a box grater (catch the juices) and stir it into the buttermilk mixture along with the minced jalapeños.
Pour the wet mixture into the dry ingredients and fold with a spatula just until no dry streaks remain. The batter should be thick but spoonable. Cover and chill for 15 minutes to hydrate the cornmeal and firm the batter slightly.
While the batter rests, heat the oil in a heavy pot or Dutch oven over medium to medium-high heat to 360°F. Set a wire rack over a paper towel–lined baking sheet beside the stove.
Give the rested batter one gentle fold. Drop a small test spoonful into the oil and fry 2 to 2 1/2 minutes, turning as needed, until richly golden and crisp. Taste and adjust the batter with a pinch of salt, a splash of buttermilk (if too thick), or a spoon of cornmeal (if too loose), as needed.
Working in batches, scoop heaping tablespoon portions (about 1 ounce) with two spoons or a small scoop and slide them into the oil. Fry 2 to 2 1/2 minutes total, turning occasionally, maintaining 350–365°F so they cook through without getting too dark.
Transfer cooked hush puppies to the rack to drain. While hot, sprinkle with a tiny pinch of salt if desired. Repeat with remaining batter, letting the oil return to temperature between batches.