Onion relish for sausages

Ingredients:

• 2 medium onions
• 1/4 cup vegetable oil
• 1 teaspoon freshly ground black pepper
• 1 tbsp crushed red pepper flakes
• 3 cloves fresh garlic, minced
• 1 cup light brown sugar
• 1.4 liters of root beer
• Fried sausages
• Hot mustard, for serving
• Mayonnaise

Preparation:

1. Peel the onion, halve it, and slice it into 2-cm-thick half rings. Place the onion and vegetable oil in a large saucepan and sauté over medium-low heat until soft. Add black pepper, red pepper flakes, garlic, and brown sugar and stir to combine.
2. Add half the root beer and simmer until the sauce begins to thicken. Add the remaining root beer and continue simmering until the liquid has almost completely evaporated.
3. Serve the relish over natural casing sausages with a good hot mustard and a little mayonnaise.