Preheat oven to 350 F. Line 9 x 13 inch baking sheet with parchment paper, allowing extra to extend beyond edge of pan, and lightly grease paper.
In food processor, blend oats and almonds until they resemble the texture of sand. Add maple syrup, cinnamon, and salt to container, and then distribute butter evenly over top. Pulse until mixture is moist and clumps together. Place dough onto prepared baking sheet and, with damp hands, gently press into pan, pressing dough to edges. Pierce crust all over with fork and then brush with egg.
Bake for 22 to 25 minutes or until crust is golden brown on edges and slightly soft to the touch in center, rotating pan from back to front halfway through. Let crust cool on pan for 10 minutes, then carefully transfer to cutting board.
To make fool, place raspberries and sugar in small saucepan. Cook over medium-low heat, stirring occasionally, until raspberries have begun to break down, about 5 minutes. Remove from heat, stir in lemon juice, and cool completely before using.
In large bowl, place whipping cream and whip into soft peaks with electric mixer or handheld metal whisk. Gently fold in yogurt, orange zest, vanilla, and cooled raspberry mixture.
Just before serving, spread fool over tart crust and garnish with dark chocolate and mint. Slice into 12 pieces.
Per serving: 369 calories; 10 g protein; 23 g total fat (9 g sat. fat); 34 g total carbohydrates (14 g sugars, 7 g fiber); 109 mg sodium