Preheat oven to 325°F and grease a 9-inch springform pan, then line the bottom with parchment paper.
Whisk together almond flour, baking powder, and salt in a medium bowl and set aside.
In a large bowl, beat butter and sugar until light and fluffy, then add eggs one at a time, beating well after each addition, and stir in vanilla and lemon zest.
Fold in the almond flour mixture until just combined, pour into prepared pan, and bake for 35-40 minutes until golden and a toothpick comes out clean, then cool completely.
For the compote, combine fruit, sugar, lemon juice, and cornstarch in a saucepan and cook over medium heat for 10-15 minutes until fruit breaks down and mixture thickens, then cool and serve over sliced cake.