This is something I do that doesn't need a recipe.
Rather than buy a bottle of lemon juice, I buy a bag of fresh lemons
or 'citrons' in French.
Pay no attention to the brand, 'Bee Sweet'; it is misleading as
far as lemons go.
Squeeze out the juice and strain; pour into ice cube trays and freeze.
The ice cube trays will not be stained.
After they are frozen, slip them out of the trays onto a
sheet of wax paper.
Put them into a zip-lock bag and back into the freezer.
I love the convenience of having lemon cubes of various sizes
at my disposal whenever a recipe calls for lemon.
They don't take much space and they stay fresh for a long time.