The cooking containers were stacked inside each other when they were warm. This can cause them to become stuck together.
Pour hot water over the cooking containers.
Take hold of the outside edge of one of the cooking containers with your fingers and try to create a gap between them.
Separate the cooking containers.
If the cooking containers still will not come apart, repeat the process.
Always place a tea towel or a sheet of kitchen roll between the cooking containers for storage, see Figure 1 and Figure 2.
Do not forcibly stack the cooking containers.
