Make the dry mix: In a medium bowl, whisk tomato powder, dried onion, garlic, basil, oregano, red pepper flakes, sugar, salt, pepper, parsley, and citric acid until evenly combined.
Package it up: Transfer the mix to an airtight jar or a zip-top bag. Label with “Dehydrated Pasta Sauce,” the date, and rehydration directions.
Rehydrate for stovetop: In a saucepan, whisk 1/2 cup dry mix with 1.25 cups water and 2 tablespoons olive oil.
Bring to a gentle simmer over medium heat, stirring. Cook 4–6 minutes until smooth and slightly thick. Add more water if you want it looser.
Adjust to taste: Taste and add a pinch more salt, sugar, or red pepper if needed.
For a sweeter, rounder sauce, stir in an extra teaspoon of olive oil or a splash of broth.
For camping or backpacking: Add 1/2 cup dry mix to a pot or mug. Pour in 1.25 cups boiling water and 1–2 tablespoons oil (or a pat of butter). Stir, cover, and let sit 5 minutes.
Stir again and serve.
Serve: Toss with hot pasta, spread on pizza dough, or spoon over meatballs. This makes enough for about 12–16 ounces of pasta, depending on how saucy you like it.