Preheat oven to 300F
Grease a small oven-safe casserole dish.
Chop up croissants and place in dish.
In a large bowl, whisk together eggs, sugar, milk, and salt until combined.
Pour egg mixture over croissants, covering completely.
Bake until pudding has puffed up and a toothpick inserted in center comes out clean, 40-50 minutes.
While the bread pudding is in the final stretch of cooking, combine all sauce ingredients except vanilla in a medium saucepan over medium heat.
Heat, stirring occasionally, until mixture thickens and comes to a full boil, about 5-7 minutes. Remove from heat and stir in vanilla.
Spoon warm pudding into individual dessert dishes; serve with sauce.