2) Process graham crackers in food processor until fine crumbs. Put in bowl and mix in chopped pecans, butter and salt. Pat into 23cm pie pan. Pre-bake crust on bottom third rack of oven for 12 mins.
2) For the date layer: Coarsely chop dates, then saute dates in butter for several minutes until caramelised; sprinkle with salt. In food processor, pulse pineapple and 30ml double cream. Add dates and process again until chunky.
3) For the cream: Mix sour cream, sugar and vanilla until well incorporated.
4) Spread date mixture evenly over pre-baked crust. Spread cream layer evenly over date mixture. Bake in middle of oven for 25 mins at 160C/Gas 4 until filling jiggles only slightly in the middle. Cool immediately in refrigerator or on dry ice at least 40 mins until filling has cooled down and set.
5) For the topping: Whip cream, vanilla and sugar until semi-firm peaks form. Spread a 0.5cm layer of whipped cream over top of pie. Slice dates and roll in sugar. Garnish pie with sliced dates, chopped roasted pecans, and pipe remaining whipped cream decoratively.