Step 1

Make the pound cake: Preheat the oven to 350°. Grease and flour a 9-by-5-inch loaf pan. In a medium bowl, toss the blueberries with the sugar, mashing slightly to release some of the juices. Let them sit at room temperature for 30 minutes, stirring occasionally, to macerate.

Step 2

Meanwhile, in a medium bowl, whisk together the flour with the baking powder and salt. In a large bowl, whisk together the yogurt, olive oil, vanilla and eggs. Stir in the macerated blueberries, followed by the dry ingredients; mix until a smooth batter forms.

Step 3

Transfer the batter to the prepared loaf pan and bake until golden brown and a cake tester inserted into the center of the cake comes out clean, 1 hour to 1 hour and 10 minutes. Let cool completely, then cut into 1-inch cubes.

Step 4

While the pound cake bakes, make the grapefruit curd: In a small saucepan, whisk together the sugar, grapefruit juice, cornstarch, salt, eggs and egg yolks until smooth, then place over medium heat. Cook, stirring constantly, until thickened, 9 to 11 minutes. Remove from the heat and strain, then stir in the butter and grapefruit zest until smooth. Cool over an ice bath. Then chill until firm, 2 hours.

Step 5

Make the stewed cherries: In a medium saucepan, combine all the cherry ingredients, except the cornstarch. Bring to a simmer over medium-high heat and cook until the cherries have softened, 8 to 10 minutes. Remove from the heat.

Step 6

In a small bowl, mix the cornstarch with 2 tablespoons of juice from the cherry mixture until smooth. Then add that to the pot. Return the saucepan to the stovetop and bring the mixture to a boil. Cook until thickened, 2 minutes, and remove from the heat to cool over an ice bath.

Step 7

Make the grapefruit pastry cream: In a large bowl, combine the cream, confectioner's sugar and salt, and, using an electric hand mixer, whip to stiff peaks. Set 1½ cups of the whipped cream aside. Fold the remaining whipped cream into the grapefruit curd until smooth.

Step 8

Assemble the trifle: In a 3-quart trifle bowl, layer one-third of the pound cake cubes, followed by one-third of the grapefruit pastry cream, ¼ cup of the blueberries, one-third of the stewed cherries and 2 tablespoons of the pistachios. Repeat this layering process 2 more times to fill the trifle bowl. Spread the reserved whipped cream over the top layer, then garnish with the remaining ¼ cup of blueberries, the remaining 2 tablespoons of pistachios and the halved cherries. Serve immediately or refrigerate for up to 4 hours.