When cooking hamburgers in a toaster oven it takes around 16 minutes to fully cook the hamburgers in a toaster oven.
When cooking the hamburgers in the toaster oven it's best to thaw the hamburgers out first and then place the hamburgers on a baking sheet that usually comes with your toaster oven.
Then after 8 minutes of cooking in the toaster oven it's best to flip the hamburgers over to ensure that the other side of the hamburgers cook properly.
It should take at least 16 minutes for cooking the hamburger fully in the toaster oven.
If the hamburger is not cooked enough for you then cook it another few minutes but the hamburgers should be fully cooked after 20 minutes in the toaster oven.