Marmalade, the lovely preserves made from the pith, peel and flesh of oranges, adds citrus flavor and a bit of pleasant bitterness to these simple muffins. Poppy seeds are visually appealing and add a nice crunch. Because of their high oil content, they can spoil easily, so be sure to give your poppy seeds a sniff before adding them to the batter.
Fresh seeds will smell nutty while rancid seeds will smell acrid. Store them in an airtight container in the freezer to keep them fresh longer.
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