Preheat oven to 400F. In a saucepan,
melt butter over moderate heat and
stir in sugar until dissolved.
Add pineapple, stirring well to incorporate.
In a bowl, whisk together eggs, milk,
half and half, reserved pineapple juice,
salt, cinnamon and vanilla.
Lightly grease a 13 x 9 pan and
spread pineapple mixture evenly over bottom.
Dip bread slices into milk mixture and
arrange in one layer on top of pineapple mixture.
Bake french toast in middle of oven
20-25 minutes or until bread is golden.
French toast can be made a day ahead of time,
covered with plastic wrap and stored
in the refrigerator. Serves 4.