Take the butter out of the fridge and heat the oven to 350 ℉. Butter a 9-inch cake tin and line it with parchment paper. (If using an 8-inch cake pan, make sure you have parchment paper handles to assist with lifting the cake from the pan later.)
Cream the butter with the sugar until it is fluffy and the color of a latte. Add the eggs one at a time, beating and scraping down after each addition. Ignore splitting.
Measure the almond flour, whole wheat flour, baking powder and salt directly into the sugar/butter/egg mixture and stir to combine.
Spoon the batter into the lined tin (it doesn't look like enough, but it will be). Choose the two ripest peaches in your fruit bowl and, holding each one over the batter, tear it into pieces roughly the size of a pit. You might squash the fruit a little but the juices are dripping over the batter, so nothing is lost. Drop the peach bits onto the batter as you go. They will slump as the cake bakes leaving sweet stains in their paths. Bake for 25 minutes.
While the cake is baking, make the almond topping. Melt the butter and stir in 3 tablespoons of the sugar, the salt, flaked almonds and rosemary needles. After 25 minutes, open the oven and spoon this over the cake and sprinkle the remaining tablespoon of sugar and turbinado sugar (if using) over everything. Continue to bake for another 20-25 minutes until the center is firm and the crust golden. Let the cake cool slightly in the tin before lifting it by the side of the parchment paper and moving to a plate. Slice and eat warm.
Eat with sour cream, Greek yogurt, creme fraiche or pour on heavy cream.
