Preheat oven to 180°C
Grind nuts until almost flour-like with a bit of texture remaining
Mix nuts, flour, ground oats, cinnamon (and cardamom if using), and salt
Work in date paste until crumbly
Add vanilla and just enough plant milk to bring mixture together
Press firmly into 23cm tart pan with removable bottom
Bake 15-18 minutes until golden and fragrant
Cool completely
Drain soaked cashews well
Blend cashews, date paste, lemon juice, zest, plant milk, and vanilla in high-speed blender for 2-3 minutes until completely smooth
Taste and adjust lemon if needed (should be quite punchy)
Pour into cooled crust
Refrigerate 4+ hours or overnight until fully set
Top with fresh raspberries just before serving
Alternative filling options if preferred:
Cornstarch version (for creamier, lighter texture):
Blend all filling ingredients with 15g cornstarch. Pour into saucepan and heat gently, stirring constantly, until mixture thickens (don't boil). Pour into baked crust and chill 4+ hours.
Agar version (for firmer set):
Blend filling ingredients with 3-4g agar powder. Heat mixture to boiling, stirring constantly. Simmer 3-5 minutes until agar fully dissolves. Work quickly to pour into crust before it begins to set (around 40°C). Chill 2+ hours.