If possible, leave the slices of bread on a baking tray, uncovered, overnight to dry out before cooking.
Set the frozen mixed berries aside to defrost. Combine the eggs, skimmed milk, vanilla extract, honey and cinnamon in a bowl with a whisk.
Add a ½ a tbsp of olive oil into a large non-stick frying pan on a medium heat. One by one, dunk the stale pieces of bread into skimmed milk/egg mix and transfer into the frying pan, frying 2 pieces at a time.
After around 3 minutes, or until golden brown, rotate and repeat the frying process on the other side. Transfer to the oven whilst completing dunking/frying the rest of the pieces of bread. For each two pieces of bread, use around ½ a tbsp of olive oil for frying.
Serve the french toast with a dollop of Greek yogurt, a handful of mixed berries, a squeeze of honey and an extra sprinkle of cinnamon.