To make the pastry, place flours and sugar into a food processor and process until combined. Add butter blend spread and process until mixture resembles breadcrumbs. Add vanilla and 2 tbs iced water; process until mixture comes together. Turn onto a floured surface and gently knead until smooth. Cover with plastic wrap and refrigerate for 30 minutes.
Meanwhile, separate egg. Place yolk in a bowl with ricotta, 1 tbs flour and sugar.
Preheat oven to 220°C. Roll the pastry out on a large piece of baking paper to a 30cm disc. Spread marmalade over pastry, leaving a 4cm border. Spread ricotta mixture over marmalade. Fold pastry edge in, pleating as you go. Pile grapes in the centre. Brush some egg white over pastry edge and grapes. Sprinkle combined almonds and sugar on top.
Bake crostata for 25 minutes until pastry is cooked through and golden. Cut crostata into wedges and dollop yoghurt on top. Serve with remaining yoghurt.