Blood orange marmalade

Remove the green stem end and peel the zest from the blood oranges; a little pith is fine. For a stiffer, more bitter marmalade use the entire peel.

Cover the peels with cold water in a saucepan, bring to a simmer on high, then hold a gentle simmer 45 minutes to an hour until very tender.

Halve and juice the oranges with a citrus press, then a reamer for more juice and pulp.

Measure the juice and add exactly half that volume of cold water.

Strain the peels, discard the water, keep the pan. Cool the peels until they can be handled, then slice thin.

Add the zest to the juice, measure the total volume, and add an equal volume of white sugar. Add lemon juice if using.

Return to the saucepan over medium-high, stir, and bring to a simmer; reduce to medium-low and cook, stirring occasionally, 30 to 40 minutes until slightly reduced and thickened, about 225F on a thermometer.

Pour into a sterilized jar; it thickens as it cools. Cool to room temperature, seal, and refrigerate overnight.

Serve spooned over toasted, buttered English muffins or crumpets.