Tonkotsu Recipe

Blanch bones

Place pork bones and optional trotters in a large stockpot and cover with cold water. Bring to a rolling boil over high heat. Boil vigorously for 10 minutes to remove blood and impurities. Drain bones and thoroughly rinse under cold running water, scrubbing any residual scum.

Roast aromatics (optional)

While bones blanch, char the halved white onion, smashed ginger, and peeled garlic cloves in a dry pan or under a broiler until lightly blackened (about 8–10 minutes). This adds depth but can be skipped for a cleaner broth.

Initial simmer

Return cleaned bones to the stockpot. Add about 6 quarts fresh water to cover. Add the roasted aromatics, scallion greens, and kombu (if using). Bring to a simmer over high heat, then reduce to a very vigorous simmer (small rolling bubbles). Do NOT allow a gentle simmer—tonkotsu requires a high boil to emulsify marrow into the broth.

Skim then maintain rolling boil

For the first 30 minutes, skim any foam and impurities that rise. After that, maintain a steady rolling boil, uncovered, for 8–12 hours. Add water as needed to keep bones mostly covered (about 6 qts total starting water will reduce). Stir occasionally and gently agitate bones to help marrow and collagen break down into the liquid.

Finish broth

After 8–12 hours the broth should be thick, milky, and opaque. Remove large bones and strain broth through a fine-mesh sieve into a clean pot. Season with 2 teaspoons sea salt to taste. Keep warm. If fat separation occurs, vigorously whisk or use an immersion blender briefly to achieve a smooth, emulsified texture.

Combine 1 cup soy sauce, 1 cup water, 1 tablespoon mirin, and 1 tablespoon sake in a small saucepan. Add the bonito flakes and bring just to a gentle simmer for 3 minutes. Remove from heat and steep for 10 minutes. Strain out bonito flakes and cool. Store tare at room temperature or refrigerate. For each bowl, use about 2–3 tablespoons tare (adjust to taste).

Roll and sear

Roll the pork belly tightly and tie with kitchen twine into a log. Pat dry. In a hot skillet, sear the belly on all sides until browned to develop flavor (2–3 minutes per side).

Braise

In a saucepan, combine 1/2 cup soy sauce, 1/4 cup sake, 1/4 cup mirin, 1/2 cup water, 2 tablespoons sugar, 3 smashed garlic cloves, 4 slices ginger, and 1 scallion. Bring to a simmer, add the seared pork belly, cover, and braise gently for 1.5–2 hours, turning every 20–30 minutes, until fork-tender. Reduce liquid uncovered in the last 10–15 minutes if you want a thicker glaze.

Rest and slice

Remove pork belly from braising liquid and let rest until cool enough to handle. Reserve braising liquid to use as additional flavor for bowls or to marinate overnight. Slice into 1/4-inch rounds before serving.

Prepare eggs

Soft-boiled eggs: bring a pot of water to a rapid simmer. Gently lower eggs and cook 6–6.5 minutes for jammy yolks. Transfer immediately to an ice bath for 5 minutes. Peel and optionally marinate in some reserved tare or braising liquid for 2–4 hours for flavor.

Cook noodles

Bring a large pot of water to a rolling boil. Cook fresh ramen noodles according to package (usually 60–90 seconds) until just tender. Drain well.

Warm bowls & combine

Ladle 2–3 tablespoons of tare into each warmed serving bowl. Add about 16 oz (500 ml) hot tonkotsu broth per bowl (adjust for bowl size). Stir to combine with tare.

Assemble ramen

Place cooked noodles into each bowl. Pour hot tare-seasoned broth over noodles. Top each bowl with 2–3 slices of chashu, a halved soft-boiled egg, 1 sheet nori, 2–3 tablespoons menma, 1 tablespoon sliced scallions, a sprinkle of toasted sesame seeds, a pinch of white pepper, and a drop of sesame oil if desired.

Serve

Serve immediately while very hot. Provide extra tare on the side for those who want a stronger flavor.