Make the mashed potatoes: Place the potatoes in a medium pot; cover with cold water and season with salt. Bring to a boil and cook until the potatoes are very tender, about 15 minutes. Reserve 1/2 cup of the cooking water, then drain the potatoes and transfer to a bowl. Add 1/4 cup of the reserved cooking water and the butter and mash, adding more cooking water if needed. Stir in the cheese and jalapenos; season with salt. Cover to keep warm.
Make the chicken: Heat 2 inches of vegetable oil in a medium pot over medium-high heat until a deep-fry thermometer registers 375 degrees F. Meanwhile, whisk the flour, crushed cornflakes, thyme, cayenne and 1/2 teaspoon salt in a shallow dish; set aside. Whisk the eggs in a shallow bowl. Dip the chicken in the eggs, letting the excess drip off, then dredge in the flour mixture, pressing to coat. Working in batches, fry the chicken until golden brown and crisp, 3 to 4 minutes. Remove with a slotted spoon and transfer to a rack set over a rimmed baking sheet to drain; season with salt.
Assemble the cones: Toss the coleslaw and cilantro in a bowl. Combine the honey and hot sauce in another bowl. Fill each cone one-third of the way with the mashed potatoes, then add a piece of chicken. Drizzle with the spicy honey and layer with more mashed potatoes and chicken. Top with the coleslaw and drizzle with more spicy honey.