Preheat the oven to 325 degrees. Lightly grease a 9x13-inch pan and line with parchment paper.
In a large saucepan, melt the butter over medium-low heat, then stir in the brown sugar, cooking until the mixture is smooth and shiny.
Immediately add the mixture to the bowl of a stationary mixer fitted with a paddle. Beat the butter and brown sugar until cool.
Once cooled, add the eggs on low speed in 3 additions, scraping after each addition. Add in the honey after the eggs have been fully incorporated into the butter/brown sugar mixture.
In a separate bowl, whisk together the flour, baking powder, cinnamon, and salt. Add to mixer and mix until just combined.
Pour the batter into the pan. Sprinkle with the chopped dates, pistachios, and salt. Drizzle with honey.
Bake at 325 degrees for 20-25 minutes. Let cool before inverting onto parchment paper. Cool completely (preferably overnight) before cutting.
