1. Slice tomatoes into congruent slices; ideally about 1/4″ thick rounds
2. Arrange on a mesh lined dehydrating tray with enough room for air to circulate between the pieces (no over lapping)
3. Place in dehydrator and dehydrate at 135°F for about 10 hours
Notes
Are you wanting dehydrated diced tomatoes instead of rounds? I still recommend dehydrating them in rounds and cutting them into pieces once dried. This prevents losing a lot of the inner flesh and promotes more even drying throughout
If dehydrating halved baby/cherry tomatoes, expect to add up to 6 extra hours of dehydrating time
A mesh liner is recommended for tomatoes
Dehydrating times may vary (the water content in the tomatoes, as well as the humidity and altitude of where you live in impact the time)