Combine 1 cup of water, brown sugar, soy sauce, honey, garlic and ground ginger into a saucepan. Set the saucepan to medium heat.

Combine the corn starch with the 1/4 cup of cold water in a medium bowl. Whisk until dissolved.

Add the corn starch mixture to the saucepan and heat the sauce until it thickens. The sauce should be thick enough to coat the back of a spoon.

Place the frozen meatballs into the slow cooker. Pour teriyaki sauce and crushed pineapple over meatballs. Gently stir.

Heat on high for 2 to 3 hours or on low for 4 to 5 hours. Serve the meatballs with sesame seeds and chopped scallions.