What varnish can you use to make acrylic painted mugs food safe?

To make acrylic painted mugs food safe, you can use a food-safe epoxy resin or a food-safe polyurethane varnish. Ensure that the product is specifically labeled as food-safe and suitable for use on surfaces that will come into contact with food or beverages. Additionally, it's important to allow the varnish to cure completely according to the manufacturer's instructions before using the mugs. Always check for any specific guidelines regarding dishwasher and microwave safety as well.