1cup(3.5 ounces) Bob's Red Mill Super-Fine Almond Flour
3/4cupplus 3 tablespoons (6 ounces) Bob's Red Mill Semolina Flour
1 1/4teaspoonsbaking powder
1 1/4cups(10 ounces) unsalted butter, at room temperature
1 2/3cups(11.65 ounces) granulated sugar
zest of 1 medium lemon
4large eggs, at room temperature
1tablespoonfreshly squeezed lemon juice
1/2teaspoonpure vanilla extract
Position a rack in the center of the oven and preheat to 350 (F). Generously spray the bottom and sides of a 9-inch springform pan with cooking spray and line the bottom with a parchment paper circle; spray the parchment as well.
Prepare the rhubarb (see baker's notes) and arrange as desired on the bottom of the pan.
Use a sharp knife to split 3 cardamom pods lengthwise. Scrape the seeds into the bowl of a food processor. Add 1 cup shelled pistachios and pulse until the nuts are finely ground and resemble a coarse meal. Pour into a medium bowl and add 1 cup Bob's Red Mill Super-Fine Almond Flour, 3/4 cup plus 3 tablespoons Bob's Red Mill Semolina Pasta Flour, 1 1/4 teaspoons baking powder, and 1/4 teaspoon kosher salt. Whisk to combine.
In the bowl of a stand mixer fitted with a paddle attachment, place 1 2/3 cups granulated sugar, 1 1/4 cup unsalted butter and zest of 1 medium lemon. Beat on medium-low for 2 to 3 minutes, or until just combined, using a rubber spatula to scrape down the bottom and sides of the bowl as needed. With the mixer on low, add 4 large eggs, one at a time, only adding the next egg when the previous one is incorporated, scraping down the bottom and sides of the bowl after every addition. With the mixer on low, add 2 tablespoons rose water, 1 tablespoon lemon juice, and 1/2 teaspoon vanilla extract, beating until just combined. Gradually add the dry ingredients (from the 4th step) and beat on low until just combined.
Pour the batter over the rhubarb and use an offset spatula to smooth it evenly across the pan. Bake for 60 to 70 minutes, or until a skewer inserted into the center of the cake comes out with few crumbs attached. Cool the cake in its pan on a wire rack completely, before inverting onto a serving plate. Serve warm, or at room temperature, with a dollop of whipped cream and garnish of chopped pistachios.