If using frozen strawberries, thaw before using. Once thawed, add to a colander and get rid of all the excess liquid from them. If using fresh, chop them up roughly.
Blend strawberries and powdered sugar together. This is your near-instant sauce. Set aside.
Mix the caster sugar and ground cinnamon together on a plate and set aside.
Whisk the milk and eggs in a wide shallow bowl. I halve the bread on the diagonal but you can leave them whole if you prefer.
Divide the butter into small pieces. Heat one small knob of butter in a pan.
Dunk the bread in the egg and milk mixture. Turn them a few times in the bowl to make sure they’re not dry on the inside. Add to the pan. Fry until golden on both sides. Dredge the bread in the sugar-cinnamon coating when they’re still hot.
Repeat for the rest of the slices adding a knob of butter to the pan each time you fry the bread. Serve with the strawberry sauce.