Place the tomato slices on baking sheets or dehydrator trays, spreading the tomatoes out so that they are not stacked on top of each other.
Dehydrate the tomatoes
If using an oven, bake the tomatoes at the lowest temperature, using the oven fan if you have one. If using a dehydrator, follow the instructions for your dehydrator. (Use the low setting if there is more than one.)
You can also dry the tomatoe slices in the sun on a dry, sunny day. Cover the tomato slices with a fine mesh cloth to keep insects away. (Bring in the tomatoes at night.)
Flip the tomatoes partway through the process, especially if using the oven or sun drying.
If making powder, dry the tomatoes until they are hard and brittle. This ensures that you have thoroughly removed the moisture from the tomatoes. If they are still flexible, they likely have a tiny bit of moisture still. (For sun-dried tomato slices, they can remain flexible.)
Once the tomatoes are completely dry, store them.
Make tomato powder
Grind the tomatoes into a powder using a blender or food processor. It may be easier if you first break the tomato slices into smaller pieces. If the powder isn't fine enough, try using a coffee grinder to finish grinding the powder.
Sift the powder thrugh a sieve to ensure a fine powder. The larger bits that remain in the sieve can be blended further until fine enough to pass through the mesh.
Makes around 8 ounces.
How long does it take?
It's impossible to give you a precise time frame for how long it will take to dry the tomatoes because it will depend on a number of factors.
Type of tomato chosen
Thickness of slices
The method used (& each appliance is different.)
Storage (dried tomato slices)
Store the dried tomato slices in an airtight container, preferably one without a lot of extra airspace, in a cool, dry place. You can prolong the storage time by storing them in a dry part of the fridge. If you store them in plastic bags, try to remove as much air as possible before sealing them. If you see mold developing, toss them.(Freezing will keep them even longer.)
The dried tomato slices can also be stored in a jar, covered with olive oil in the fridge. You may want to first slice them into strips for use on salads or bread. Oil-covered tomato slices don't generally keep as long as dried tomatoes without oil.While you can add fresh herbs or garlic to the tomatoes and oil, doing so will prolong the shelf life considerably. (You should store them in the fridge and use within a few days.)To help bring out the acidic flavor of the tomatoes, dip them into vinegar before placing them into the oil. I like using dried tomatoes stored in oil for topping salads or working into spreads like hummus.
Storage (tomato powder)
Store in an airtight container in a cool, dry place.If you store it in an airtight container in the fridge, it is said to last almost indefinitely. That is, of course, if you did a good job of dehydrating the tomatoes well from the beginning.
Dehydrated tomato uses
Dried tomatoes can be used in a variety of other recipes. Depending on how you plan to use them, you can use them dried or rehydrate them in water for around 30 minutes.Sundried tomato pieces can be blended into sauces, soups, or compound butter. (Leave them dried if you'll be adding them to butter for the longest shelf life.)They can be added, sliced, to salads, sandwiches, hamburgers, or pizza. They can also be added to pasta, marinades, or scrambled eggs.Here on the blog, I used them in the Citrus-Herb Basque Chicken.
Tomato powder uses
Tomato powder is incredibly useful to have around because of its versatility. It's great for seasoning my homemade flaxseed tortilla chips so they taste more like healthier Doritos. You can also add it to soups, stews, and sauces. It's also delicious when added to ground beef for tacos and other Mexican dishes. (For Mexican dishes, try seasoning it with some garlic and cumin.)
Making tomato sauce from powder
To make a tomato sauce from tomato powder, mix the powder with water. Simmer the mixture over low to medium heat while stirring to fully dissolve the powder and thicken the sauce.
Depending upon how thick you want the final sauce to be, add around 1 part of water to 1 part tomato powder.
For more of a tomato paste, use a little less water or begin with a 1:1 ratio and simmer it down to the desired consistency.
For a thinner sauce, for something like enchiladas, add more water.