Prepare the loaf pan. Preheat the oven to 350° F. Grease an 8½" x 4½" loaf pan or a 9x5 inch loaf pan and set aside.
Soak the fruit. In a medium-sized bowl, add the chopped dates and raisins. Pour the boiling water over the fruit mixture and add one teaspoon of baking soda. Allow the fruit to soak for at least 10 minutes, do not drain.
Cream together the wet ingredients. In a large mixing bowl beat together the melted oil, dark brown sugar, and regular sugar for 30 seconds. Add the egg and vanilla extract, and cream together for another 1-2 minutes until the mixture is light and fluffy.
Add the dry ingredients. At low speed, slowly add the gluten-free flour, almond flour, baking powder, and salt. The mix will become crumbly.
Add the soaked fruit with liquid. Once all the dry ingredients are added pour in the fruit mixture with the liquid. Mix until well combined.
Fold in the nuts. Fold in the walnuts and then pour the batter into the prepared greased loaf pan.
Bake the loaf. Bake the bread for 30 minutes. After 30 minutes, cover the loaf with aluminum foil to prevent the top from over-browning. Continue to bake for another 20 minutes (50 minutes total) or until the center of the loaf comes out clean with a toothpick.
Allow the bread to cool. Remove the loaf from the oven. Let the bread sit in the pan for 10 minutes, then transfer to a wire rack to continue cooling. Cool completely before slicing, then store in a tightly sealed container at room temperature for several days.