Start with the base by mixing together the crushed biscuits, butter and pistachios. Press into the base of a line square tin using the back of a spoon. Carefully spread over the warmed pistachio paste. Next, lay half of the strawberries on top, flat side down, leaving a small space between each strawberry. To make the filling, melt together the soaked gelatin leaves and lemon juice. Place the cream cheese, yogurt, lemon zest, vanilla  and icing sugar into a food processor and blitz together. Add in the melted gelatin mixture and pulse again. Carefully pour this mixture over the strawberries, making sure there are no spaces. Tap the tin lightly on the table and place into the fridge to chill and firm up for 2-3 hours or overnight. When ready to serve, remove from the tin and place onto a serving board. Slice the remaining strawberries and decoratively place on top. Finish off with extra pistachios and fresh mint leaves.