Preheat the oven to 350ºF (180ºC). Line the bottom of 9 x 5-inch loaf pan with parchment paper. Grease and flour the inside.

In a large bowl, whisk together the flour, pistachio flour, baking powder, baking soda and salt.

In a separate large bowl, cream the butter, granulated sugar and lemon zest with an electric mixer at medium speed, until the mixture is light and fluffy. Beat in the oil gradually until it's well combined. Beat in the eggs in three separate additions, making sure each one is fully incorporated before adding the next. Beat in the extracts. Then, if using, beat in the food coloring a little at a time until your desired shade is reached.

On low speed, mix in the flour mixture in two additions, alternating with half of the sour cream after each addition. Mix just until combined. Transfer the batter to the prepared baking pan. Bake until a toothpick inserted into the center of the loaf comes out clean, about 42-47 minutes. Cool the loaf in the pan for 10 minutes, then turn it out onto a cooling rack to cool completely.

To make the fresh raspberry icing, purée the raspberries together with the lemon juice in a blender or small food processor. Strain the raspberries through a sieve. In a medium-size bowl, whisk together the raspberry purée, powdered sugar, melted butter and a pinch of salt. Spoon the icing over the cooled loaf, letting the icing drip down the sides. Sprinkle with chopped pistachios. Decorate the top with edible flowers or fresh raspberries.