Pecan and Maple Tart

This is an exceedingly rich tart, as it should be. You can substitute walnuts or even hazelnuts or almonds for the pecans, but no low-fat, low-sugar substitutes, please. If using almonds, I would leave out the maple syrup and replace it with extra corn syrup or golden syrup, keeping the flavour delicate to complement the almonds. Corn syrup can be found in shops which stock American food products such as Selfridges, the Rosslyn Delicatessen, Harvey Nichols and Jerry’s Home Store, all in Lon