Scatter ½ cup cornstarch onto a large plate or tray, season with 1 teaspoon of salt and a big pinch of black pepper and stir to combine. Add the tofu cubes and toss until coated on all sides.

Heat a large (12-inch) well-seasoned cast-iron or nonstick skillet on medium-high until hot. Drizzle with about 2 tablespoons of oil (enough to cover the base of the pan) and heat until the oil is hot, 1 to 2 minutes. Add the tofu and pan fry on each side until crispy, 1 to 2 minutes per side. Once all sides are golden, transfer the tofu to a plate.

Make the sauce: In a medium bowl, add the soy sauce, ketchup, rice vinegar, sriracha and sugar and stir to combine. Add 1 tablespoon cornstarch and ⅓ cup of water and whisk until the cornstarch is completely mixed in and the sauce is lump free.

Place the skillet back over medium-high heat. Add the remaining 1 tablespoon of oil to the pan along with the onion, ginger, garlic, and jalapeño and toss constantly until the onions have begun to soften, 1 to 2 minutes. Add the bell pepper and broccoli, season with 1 teaspoon of salt and stir fry just until the vegetables are crisp tender (or to your liking), 4 to 6 minutes. Give the sauce a quick stir and then add it to the vegetables and toss for just 20 to 30 seconds, until it has thickened up. Add the tofu and toss until it is coated in the sauce and remove from heat immediately.

To serve, top with scallions and eat with rice