Bring Brown sugar, corn syrup, butter and salt to a boil in a medium saucepan over medium-high heat, whisking to disolve sugar.
Boil until mixture is syrupy and measures 1 1/2 cups, about 3 minutes.
Remove from heat; add cream and bourbon and stir until smooth.
Let cool completely, cover and chill. Warm before serving.
Toss bread, melted butter and 2 Tbsp. sugar in a large bowl and set aside.
Using an electric mixer, beat eggs and remaining 1 1/2 cups sugar in another large bowl until pale yellow and fluffy - about 3 minutes.
Add cream, poppy seeds, and salt; beat to blend.
Place bourbon in a small bowl; scrape in seed from vanilla bean (reserve bean for another use).
Whisk to distribute seeds, then add to egg mixture, whisking to blend well.
Pour egg mixture over bread mixture.
Add pecans and dates; toss well to coat.
Transfer mixture to a 13x9x2 inch glass pan or ceramic baking dish, spreading out in an even layer.
Cover with plastic wrap and chill overnight.
Preheat over to 325 degrees.
Remove plastic wrap and bake until top is browned in spots and a tester inserted into center comes out clean - 1 1/4 to 1 1/2 hours.
Serve bread pudding with warmed sauce.