I cannot believe that you do not have the pleasure of buttertarts in the USA ( or at least in the part you live.)
My wife makes the best buttertarts...if I am correct they are close to what you have in Pecan tarts....without the nuts.
Here is her receipe
1/2 cup sugar
2 tbsp butter
1 egg
3/4 cup dried currants
1tbsp vanilla
2tbsp corn syrup
cream together butter and sugar till smooth.
add beaten egg
add remaining
mix well
spoon into tart shells
bake at 375 for 15 to 20 minutes
THEN ENJOY!!!