To prepare the French toast:
- Generously butter the bottom and sides of a 9 x 13” casserole dish.
- In a medium bowl, whisk eggs and then whisk in half and half, milk, sugar, cinnamon and vanilla.
- Submerge each piece of bread in the egg mixture and allow to soak for about 30 seconds/slice. Arrange slices in casserole dish. Pour remaining egg mixture evenly over top of bread. Cover with foil and refrigerate overnight.
To bake the French toast:
- Preheat oven to 350 degrees.
- Combine pecans, brown sugar, cinnamon and salt in a small bowl. Cut in butter pieces until the mixture resembles small crumbs. Sprinkle mixture evenly over French toast.
- Bake for 30 minutes covered and another 20-25 minutes uncovered. Cut into pieces and serve with warm Irish Cream Sauce.
To make the Irish Cream Sauce:
Combine cream, liqueur, sugar and vanilla in a small pan. Bring to a boil over medium-high heat.
Stir together cornstarch and water and add to cream mixture. Stir and continue to cook until slightly thickened, about 5-7 minutes. If not using immediately, allow to cool, cover and refrigerate. Warm before serving.