I used mostly frozen mixed berries, and picked out any larger blackberries - it’s tough to cut into a loaf with giant chunks in it. If you want more berry goodness, swirl in a few spoonfuls of berry jam when you add the berries.

Obviously lemon always, but you can eliminate the zest and extract with no other changes, if you prefer.

This is not very sweet. If you want it to be closer to a standard loaf cake, add another ⅓ cup of sugar.