Deep-fried apple slices in batter

Ingredients:

• 1 and 1/4 cups premium flour
• 3/4 cup sugar
• 1.5 tsp ground cinnamon
• 0.5 tsp fine sea salt
• 1/4 tsp baking powder
• 1/4 teaspoon of baking soda
• 3/4 cup sparkling water
• 0.5 cups of sour milk or kefir
• 1 tsp vanilla extract
• Zest of 1 large lemon
• 2 tbsp olive oil
• 2 tbsp. vegetable oil
• 3 firm apples, such as Granny Smith

Preparation:

1. Liquid batter:
   
   In a medium bowl, combine flour, 1/4 cup sugar, cinnamon, salt, baking powder, and baking soda. Add sparkling water, buttermilk, and vanilla and mix until smooth. Let sit for 15 minutes.
2. Lemon sugarIn a small bowl, combine the remaining 1/2 cup sugar and lemon zest.
3. In a 4-5 quart heavy-bottomed saucepan, heat the olive oil and vegetable oil over medium heat until a deep-fry thermometer reads 190°C (355°F) (if you don't have a thermometer, add a cube of bread; it should brown in about 3 minutes).
4. Meanwhile, peel the apples, remove the cores, then cut into 1 cm thick slices. Dry the apples with paper towels.
5. Add the apple slices to the batter and toss to coat. Deep-fry the apples, a few at a time, turning occasionally, until golden brown, 2–3 minutes per batch.
6. Transfer to paper towels to drain excess oil and sprinkle with lemon sugar while still warm. Serve immediately.