Try this Homemade Granular Vegetable Broth recipe.
Coarse salt does not merely season the vegetables; it acts as an extraction tool through osmosis. Mixing raw vegetables with coarse salt in a dry pot triggers cellular walls to release internal moisture immediately. Keep the burner on low heat during this initial phase. High heat will scorch the bottom of the vessel before the plant cells can weep their liquid. Stir the mixture frequently to distribute the brine evenly across all pieces. Cook the produce until it collapses entirely into a dense pulp. This extended reduction concentrates the natural sugars and starches required for a rich final broth.
Spread the cooked vegetable pulp onto parchment-lined baking sheets in a layer no thicker than a few millimeters. Set the oven to 100 degrees Celsius to remove the remaining moisture slowly without browning the sugars prematurely. This drying process typically requires approximately four hours of consistent heat until the sheets turn completely brittle and crystalized. Transfer the dried shards into a food processor only after they reach room temperature. Pulse the dry mixture into a uniform powder and store the finished granules in airtight glass jars to prevent ambient humidity from causing clumping.