To determine if your potato is fully cooked, you can use the following methods: Insert a fork into the center of the potato—if it slides through easily and the potato feels soft, it is likely cooked. Alternatively, gently squeeze the potato—it should give way under light pressure and feel soft all the way through. You can also check the internal temperature using a food thermometer, which should read around 210°F (99°C) to 212°F (100°C) for a cooked potato. Lastly, a fully cooked potato will have a fluffy texture inside, with slightly wrinkled skin and some separation between the flesh and skin.