Combine the soy sauce, honey, water, grated ginger, and minced garlic in a medium saucepan. Stir to combine.

Place the saucepan over medium heat and bring the mixture to a gentle simmer. Stir occasionally as it heats up.

Once simmering, gradually whisk in the cornstarch slurry. Continue whisking constantly to prevent lumps from forming.

Continue to cook and stir the sauce for another 3-5 minutes, or until it has thickened to your desired consistency. It should coat the back of a spoon.

Remove the saucepan from the heat. Let the teriyaki sauce cool slightly before using. It will thicken further as it cools.