Like Nanaimo Bars, butter tarts are a Canadian treat and all recipes are very similar. Increase the corn syrup - they will be runnier; increase the brown sugar - they will be less runny. The cooking time will also affect the texture of the filling. My daughter and granddaughter won second place in the butter tart contest at the Good Food Festival in Toronto...... and yes, I am very proud of them ....... and yes, the tarts are delicious! My granddaughter came up with the recipe name based on the display platter they used for the contest. You can leave out the raisins entirely or decrease the amount ........ try currants or pecans, or walnuts or a mixture. My grandchildren like them with chocolate chips - the choice is yours!