Cheddar and Walnut Scones with Onion Jam

Name: Cheddar and Walnut Scones with Onion Jam
Prep time: 25 min
Cook time: 1 h 45 min
Total time: 1 h 45 min
Yield: 6 portions
Ingredients: 16 oz red onions; 12 oz sugar; 3 ½ oz red wine vinegar; 1 oz white wine; 1 oz raisins; ½ tsp ground cinnamon; 3 whole cloves; ¼ tsp salt; 3 oz cheddar cheese; 2 oz walnut pieces; 1 tsp dried rosemary; 8 oz all-purpose flour; 2 tsp baking powder; 1 tsp salt; ¼ tsp cayenne pepper; ¼ tsp mustard powder; 1 large egg; 3 oz whole milk; 1 oz extra virgin olive oil