Preheat the air fryer to 400°F (200°C).

Prepare Air Fryer French Fries: Scrub the russet potatoes and cut them into thin, uniform strips. Place them in a bowl of water to soak for a few minutes then drain well. In a bowl, toss the potato with olive oil, garlic powder, paprika, salt, and pepper, ensuring they are evenly coated. Place the seasoned potatoes in the air fryer basket and cook at 400°F (200°C) for about 15 minutes, shaking or flipping them halfway through, until the fries are crispy and golden.

Prep the Bratwurst: Heat a large skillet over medium-high heat. Add the vegetable oil to the skillet. Sear the bratwurst, about 5-7 minutes, turning occasionally until they are browned and cooked through, to an internal temperature of 155°F (68°C) using a thermometer.

Make the Curry Ketchup: While the sausages are cooking, in a separate saucepan, heat a bit of vegetable oil over medium heat. Add the finely chopped onion and sauté until translucent, about 3 minutes. Stir in the minced garlic and cook for another 1 minute until fragrant. Add the curry powder, paprika, cayenne pepper, salt, and black pepper to the onion and garlic mixture. Cook for an additional 2 minutes, stirring constantly to toast the spices. Pour in the tomato ketchup and water into the saucepan. Stir well to combine all the ingredients.

Allow the sauce to simmer over low heat for about 5-7 minutes, stirring occasionally.

Slice the Bratwurst: Once the bratwurst sausages are cooked through, remove them from the skillet. Slice them into bite-sized pieces.

Mix all the ingredients for the lemonade. Serve over ice.

Pour the curry ketchup sauce over the sliced bratwurst. Toss the sausages in the sauce until they are well-coated. Serve with a side of french fries and homemade lemonade.