Rich Stock Concentrate

Method

1. Place bones in a large stockpot. Add vegetables, herbs, vinegar, and enough cold water to cover by 1 inch.
2. Bring to a boil, then immediately reduce to a bare simmer (small bubbles just breaking the surface). Skim any scum that rises during the first 30 minutes.
3. Simmer uncovered for 4-6 hours. The longer, the richer. (For a pressure cooker: 90 minutes at high pressure.)
4. Strain through a fine-mesh strainer. Discard solids.
5. Return the strained stock to a clean pot. Bring to a boil and reduce by 75-80%, until you have about 475 ml (2 cups) of concentrated, syrupy stock. This will take 1-2 hours. Watch it closely as it reduces.
6. Let cool. It should be deeply colored and gel when refrigerated (like Jello).
7. Pour into ice cube trays. Freeze solid, then pop out and store in a zip-top bag.
8. *To use:** Add 1 concentrate cube to 240 ml (1 cup) boiling water for broth. Use directly in sauces and risottos for intense flavor.
9. *Storage:** Freeze for up to 6 months.