Create Lava

You transform a patch of earth into burning lava. You choose a 5-foot square of earth or stone that you can see within 30 feet, transforming it into a pit of lava up to 1 foot deep. A creature takes 3d10 fire damage when it enters lava for the first time on a turn or when it ends its turn there. The lava is considered difficult terrain, and solidifies back into solid earth after 1 hour. 

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, you can transform 1 additional 5-foot square of earth adjacent to another square of lava for each level above 2nd.