You can leave it to set completely and then cut to suitable shapes.
This is the easiest method for making mango burfi.
I have made this from homemade khoa you can buy a storebought one which is readily available.
you can use fresh mango pulp or a tinned mango pulp.
In case you are using thick bottomed kadai add some ghee inbetween if necessary to prevent sticking,but if using nonstick kadai ghee is not needed.