Preheat the oven to 350°F (180°C), or 160°C if using a fan oven.
Spread raw walnuts on a sheet pan, and toast for 7 minutes. Remove, allow to cool and chop into smaller pieces.
In a medium bowl, whisk together the flour, baking powder, and salt. Set aside.
Soak the dates: In a separate bowl, pour the boiling water over the chopped dates. Let them soak until the mixture cools to room temperature. Once cooled, stir in the baking soda.
To the date mixture, add the olive oil, brown sugar, eggs, and vanilla. Whisk until well combined.
Gradually add the dry ingredients to the wet mixture, stirring until just combined. Fold in the chopped walnuts.
Grease and line a 9x5-inch (23x13 cm) loaf pan with parchment paper. Pour in the batter and smooth the top.
Bake for 40-45 minutes, or until a toothpick inserted in the center comes out clean and the internal temperature reaches 200°F (93°C).
Let the bread cool in the pan for 10 minutes, then transfer to a wire rack to cool completely before slicing.