Servings: Makes 2 quarts
In a large, heavy-bottomed saucepan, heat the oil until smoking. Add the chicken or capon pieces and brown all over, stirring to avoid burning.
Transfer the browned capon parts to a bowl, then add the carrots, onion and celery to the pan and cook until soft and browned.
Return the bird to the pan and add 4 quarts of water, the tomato paste, peppercorns and parsley, stirring to dislodge the browned meat and vegetable bits from the bottom of the pan. Bring almost to a boil, reduce the heat, and cook at a low simmer for 2 hours, until reduced by half, occasionally skimming off the fat.
Strain the stock, pressing the solids with the bottom of a ladle to extract all the liquid. Cool, then refrigerate or freeze until ready to use.