Prepare the mashed potato with butter and hot milk and beat until fluffy. Season with salt and pepper.
Cook onions in olive oil for 10 minutes or until soft and golden. Add Kikkoman Soy Sauce and continue cooking until caramelized. Add flour to form a roux base then gradually add chicken stock, mustard and wine to thicken.
Brush sausages with oil and grill.
Heat extra virgin olive oil over medium/high heat and saut_ spinach with thinly sliced garlic and Kikkoman Soy Sauce until soft.
Serve sausages with mash, saut_ed spinach and top with onion gravy.