Easy Homemade Mushroom Burgers

Name: Easy Homemade Mushroom Burgers
Cuisine: American
Ingredients: 120g (2 cups) mushrooms; 1 red onion; 2 tbsp oil (I used olive); 2 tsp Worcestershire sauce; ½ tsp ground paprika; ¼ tsp garlic powder; 2 tbsp flour (I used wholemeal spelt); 30g (heaped ⅓ cup) breadcrumbs; 20g (¼ cup) oats; ½ tsp salt; ½ tsp pepper; ½ tsp oregano; 40g (1½ oz) cheddar cheese (grated/shredded); 1 egg (large - approx. 60g)