Prepare the ingredients as instructed.
Preheat the air fryer to 400°F (200°C).
To prepare the iced ginger tea, bring water to a gentle simmer, then remove from heat. Add the ginger tea bags and steep for about 10 minutes. Remove the tea bags. Refrigerate until chilled, then pour over ice cubes.
In a bowl, toss the potatoes with extra-virgin olive oil, garlic powder, paprika, salt, and black pepper until evenly coated.
Place the potatoes in the air fryer basket in a single layer. Cook at 400°F (200°C) for about 20 minutes, shaking halfway through, until golden and crispy.
Preheat the oven to 400°F (200°C). Place the bratwurst on a baking sheet and bake until fully cooked and the internal temperature reaches 165°F (74°C). Remove from the oven and slice into bite-sized pieces.
While the bratwurst are baking, heat oil in a saucepan over medium heat. Add the finely chopped onion and sauté until translucent. Add the minced garlic and cook briefly until fragrant. Stir in curry powder, paprika, cayenne pepper, salt, and black pepper. Cook briefly to toast the spices. Add ketchup and water, stirring to combine. Reduce heat and simmer until slightly thickened.
Add the sliced bratwurst to the sauce and toss until evenly coated.
Serve the currywurst with French fries and iced ginger tea.