In a small saucepan, combine the kombu, katsuobushi, mirin, and rice vinegar. Cook on low until the mixture just simmers, stirring occasionally. Remove from heat and let cool for about 10 minutes.

Once the mixture is cooled, strain it to remove the katsuobushi and kombu. Pour the flavorful liquid into a jar for later use.

Add the soy sauce and yuzu juice to the jar. Secure the lid tightly and shake until well combined, creating a harmonious blend of flavors.

In a small bowl, mix the yuzu ponzu, soy sauce, and minced garlic. Stir gently and let it sit while you prepare the hamachi for optimal flavor infusion.

Take the hamachi and slice it against the grain at a 45° angle into thin pieces. Arrange the slices beautifully on a plate and top each with a slice of jalapeno for a bit of heat.

Generously drizzle the yuzu ponzu sauce over the hamachi. Finish by garnishing with ikura and lemon slices. Serve with a side of wasabi for an extra kick!