Can you prepare muffin batter the night before, store in the refrigerator, and bake off the next morning?

--Brad

You can prepare muffin batter ahead of time.   I'm not sure I would want to leave a batter with whole, uncooked eggs too long, but you should be safe if you are using fresh eggs and you cook the batter within 48 hours.

Because some  of the carbon dioxide bubbles that make the muffins rise when cooked will escape as the batter sits, they may be slightly denser than if they had been cooked immediately after the batter was mixed.

To use the batter, simply preheat the over as required for your recipe and then spoon the batter into muffin tins or cups and cook as usual.  Do not stir the batter, as this will force out more of the carbon dioxide bubbles.  If the batter has separated, gently fold the ingredients back together.  The muffins may take a couple of minutes longer to cook, since the batter starts out colder.

You can also freeze muffin batter in paper muffin cups for later use.  Fill the cups as you would normally, and then freeze them while still in the muffin pan to hold their shape, until solid.  Transfer them to a resealable plastic bag and keep frozen until you are ready to use them.  To use, preheat your oven, place as many muffins as you need into a muffin pan and cook.  They will take about five minutes longer than if they were being made fresh.