- Preheat oven to 375°F. Line an 8-inch-square baking pan with parchment paper, leaving a 1-inch overhang on two sides.
- Pulse together flour, butter, and 1/2 cup sugar in a food processor until a sandy texture forms, 10 to 12 times. Transfer 1/3 cup to a bowl, and fold in almonds and 1/2 cup oats. Squeeze together to form small clumps; chill.
- Add baking soda, salt, and remaining 1 cup oats to mixture in food processor. Pulse until incorporated, 12 to 15 times. Press into bottom of prepared pan. Bake until golden brown, 14 to16 minutes.
- Mash together 1 container raspberries and remaining tablespoon sugar in a bowl. Spread over prebaked crust. Scatter remaining container raspberries and chilled crumb mixture on top.
- Bake until golden brown, 40 to 45 minutes. Cool in pan 30 minutes, then use overhang to transfer to a wire rack to cool completely.