Mirin is the only ingredient that demands a special trip, available at Harris Teeter's Asian section or a dedicated Asian market, but it's a pantry staple worth keeping for future use and not prohibitively expensive. The remaining ingredients—ketchup, Worcestershire, soy sauce, Dijon mustard, sugar, garlic powder—are standard stock at any Charlotte chain including Food Lion, Walmart, and ALDI, making this a true weeknight solution. The stated 5-minute time is honest and accurate; you're simply whisking together seven common items. This sauce costs under $2 total to make and keeps refrigerated for weeks, making it far cheaper than store-bought tonkatsu sauce and infinitely better on tonkatsu, pork cutlets, fried chicken, or fries.