Peel and cut potatoes into 1-inch steak fry–style pieces.
Soak in water for 15 minutes, then drain and pat dry.
Mix together the seasoning ingredients, sugar, salt, MSG, black pepper, and Chinese five spice in a small bowl. Set aside.
In another bowl, whisk together the curry sauce ingredients until smooth.
Heat oil to 350°F and fry the potatoes for 5 minutes until lightly golden. Remove and let cool for 15–20 minutes.
Meanwhile, melt butter in a saucepan, add the curry sauce mixture, and bring to a boil, stirring constantly until thickened. Remove from heat.
Increase oil temperature to 400°F and fry the potatoes again for 3–4 minutes until golden and crispy. Drain well.
Heat 1 tablespoon oil in a wok.
Sauté onions, bell peppers, jalapeños, and garlic for 1 minute until fragrant but still crisp.
Add fries and seasoning blend, then toss to coat evenly.
Serve as is, with curry sauce on the side, or smothered in curry sauce.
