01 - Preheat the oven to 350°F. Line two baking sheets with parchment paper for easy cleanup and to prevent sticking.
02 - Combine the chopped dates and boiling water in a small bowl. Stir in the baking soda and let the mixture sit for 10 minutes to allow the dates to soften completely.
03 - In a large bowl, beat the softened butter, dark brown sugar, and granulated sugar together until the mixture is light and fluffy, approximately 2-3 minutes.
04 - Beat in the egg and vanilla extract until fully incorporated into the butter mixture.
05 - In a separate medium bowl, whisk together the all-purpose flour, baking powder, and salt until evenly distributed.
06 - Add the dry ingredient mixture to the wet ingredients and mix just until combined. Be careful not to overmix.
07 - Fold the softened date mixture and its soaking liquid into the dough until evenly incorporated throughout.
08 - Drop tablespoon-sized scoops of dough onto the prepared baking sheets, spacing them approximately 2 inches apart to allow for spreading during baking.
09 - Bake for 10-12 minutes until the edges are set but the centers still appear slightly underbaked. Allow the cookies to cool on the baking sheet for 5 minutes before transferring to a wire rack.
10 - While cookies cool, melt the butter and brown sugar in a small saucepan over medium heat, stirring constantly until dissolved. Add the heavy cream and salt, bring to a simmer, and cook for 1-2 minutes until slightly thickened. Remove from heat and stir in the vanilla extract.
11 - Drizzle the warm toffee glaze over the cooled cookies. Allow the glaze to set before serving.