Heat oven to 375 degrees. Put almond flour, sugar, eggs, almond extract and salt in a blender. Blend at medium speed for a minute or so, until well combined. Scrape bowl as necessary. Add half and half and blend again. (You can use a blender or a stick blender.)
Butter a 10-inch round pan or a cast iron pan (pyrex is great so you can check the browning on the bottom.) Arrange raspberries over the bottom of the dish.
Pour batter over the berries. Bake on the top oven rack for 30-35 minutes, until puffed and slightly browned on top. (A knife inserted in the center should come out clean.)
Cool clafoutis to room temperature. Sprinkle with powdered sugar and serve in wedges from the dish.
Notes
Traditionally, a clafouti is made with sour cherries, but you can use any berry or stone fruit. Consider ,ixing your raspberries with blueberries, or creating a spiral of nectarines and plums.