Start by cutting and drying all of your ingredients, then thread them onto bamboo skewers. For smaller ingrients like quail eggs or shrimp, you can stack 2-3 on one skewer (however, keep in mind the depth of your cooking oil).
Take a small saucepan and add 80 ml Worcestershire sauce, 60 ml dashi stock, 1 tbsp sugar, 1 tbsp mirin, 1 tbsp red wine and 1 tsp tomato ketchup. Mix well and boil for 1 minute over a medium heat, then set aside for later.
Start heating oil for deep frying to 170 °C (338 °F) to 180 °C (356 °F). While you wait, combine 150 g all-purpose flour, 250 ml cold water and 1 egg in a large mixing bowl until smooth. Prepare one more plate with 150 g panko breadcrumbs.
When your oil is ready, dip the skewered ingredients into the batter one at a time before rolling in the panko breadcrumbs. (Tip: If your ingredients are slippery, it can be worthwhile to coat them in a light dusting of flour before battering.)
Once fully coated in breadcrumbs, carefully place the skewers into the oil and fry for approximately 3 minutes or until golden. (This time is an estimate and depends on the thickness of your ingredients.)
Fry in small batches to avoid lowering the oil temperature too much. I recommend frying each ingredient at the same time (e.g. meat together, vegetables together etc.)
Remove the cooked skewers from the oil and transfer them to a wire rack to drain.