Gather the ingredients.
Peel and chop 1 garlic clove .
In a small saucepan, combine ¼ cup soy sauce , 2 tablespoons mirin , 2 ½ tablespoons granulated sugar , 2 teaspoons sesame oil , and the chopped garlic.
Heat over medium to high heat until sugar dissolves—about 3 minutes. Stir constantly to help dissolve sugar and prevent burning. Allow sauce to cool for about 5 to 10 minutes.
Optionally, use a strainer, pour sauce into a small bowl to separate garlic pieces. You can also leave it in the sauce if you prefer.
Add 1 ½ teaspoons ground roasted white sesame seeds and ½ teaspoon whole roasted sesame seeds to the strained sauce. Mix gently.
The yakiniku sauce is now ready to use. Use to dip meats and vegetables, or as a sauce to pour over meat.
