Gather all the ingredients. Break the boxed roux into cubes and use 2 cubes Japanese curry roux (keep the leftovers in an airtight container and store in the refrigerator/freezer for 1–3 months). Prepare 3 cups dashi (Japanese soup stock) using your preferred method.

Thinly slice ½ onion and 2 green onions/scallions. Set aside the green onions for garnish.

Preheat a medium pot or Dutch oven (I used a 2.75 QT Staub) over medium heat. When the pot is hot, add 1 Tbsp neutral oil. Next, add the onion slices.

Sauté the onion slices for 2–3 minutes. Then, add 6 oz thinly sliced pork loin that you‘ve cut into bite-sized pieces.

Cook the meat until it‘s barely pink. Next, add 1 Tbsp sake.

Add the dashi to the pot and cover with the lid. Reduce the heat to medium low and cook for 5 minutes.

When simmering, skim off the scum and fat from the stock with a fine-mesh skimmer and continue to cook.

Meanwhile, start boiling a large pot of water for the udon.

After 5 minutes of simmering the stock and meat, turn off the heat. Next, put a cube of curry roux in a ladleful of hot stock.

With chopsticks or a spoon, dissolve the roux cube completely in the ladle, then release it to the soup. Repeat with the next cube. Tip: You don‘t want to eat a chunk of undissolved curry roux, so take your time to dissolve it completely.

Add 2 tsp soy sauce and mix well. Turn off the heat and cover with the lid to keep it warm.

When the water is boiling, cook 2 servings udon noodles according to the package instructions (for this Sanuki udon, I heated the frozen noodles in boiling water for 1 minute).

Drain the noodles and divide into two bowls. Pour the curry soup over the udon noodles. Top with the green onions and serve immediately.

Keep the leftover curry soup in a glass airtight container and store it in the refrigerator for up to 3 days and in the freezer for a month. Defrost in the refrigerator for 24 hours and reheat in a pot. I recommend cooking the udon noodles just before serving.