Gluten-Free Onion Rings

• 3 large brown onions, sliced into rings
• 300 g gluten-free plain flour
• 2 tsp baking powder
• Salt and pepper, to season
• 0.5 tsp smoky paprika
• 2 eggs, lightly beaten
• 500 gluten-free beer

Horseradish sauce

• 115 g mayonnaise
• 125 ml sour cream
• 3 tsp horseradish cream or 1.5 tsp prepared horseradish
• 2 tbsp tomato ketchup
• 0.25 tsp paprika
• 0.25 tsp salt
• Pinch of dried oregano
• Pinch black pepper
• Pinch cayenne pepper