1 cup sourdough starter, unfed
1 teaspoon sugar
1/4 to 1/2 teaspoon salt
1/2 teaspoon baking soda
Place the starter in a medium-sized bowl. Sprinkle the sugar, salt, and baking soda over the surface. Whisk together. The batter should rise up, becoming the consistency of whipped cream.
Heat your griddle over medium-low heat. Lightly grease the surface.
To make crumpets, lightly grease English muffin rings (1″ high and 4″ across) and place on the griddle. Scoop the batter into the rings, filling them about 1/4″ deep. Cook over low heat until the tops are set and full of small holes. Remove the rings and flip the crumpets over for a minute or two.
Toast the crumpets to brown and crisp them before serving with butter and jam.
Store any leftovers at room temperature for several days. Freeze for longer storage — up to 3 months.