1Heat oven to 325°F. Spray 10 (4-oz) custard cups or individual baking dishes (ramekins) with cooking spray. Place on cookie sheet.
2In 2-quart saucepan, heat 3 cups whipping cream, the brown sugar and corn syrup to boiling over medium heat, stirring frequently. Boil 14 to 16 minutes, stirring constantly, until thickened and reduced to 3 cups. Pour 1/4 cup of the toffee sauce into each custard cup. In 1-quart saucepan, heat dates and water to boiling over medium-high heat. Remove from heat; stir in baking soda. Let stand 5 minutes.
3In medium bowl, beat butter and granulated sugar with electric mixer on medium speed until light and fluffy. Add egg and vanilla, beating just until blended. On low speed, beat in flour and salt alternately with date mixture until smooth. Spoon 3 to 4 tablespoons batter over toffee sauce in each cup (do not spread).
4Bake 18 to 20 minutes or until toothpick inserted in center comes out almost clean. Cool 5 minutes. Serve warm with whipped cream and remaining toffee sauce.