Preheat oven to 190ºC . Grease baking sheets with vegetable oil. Sift flour,baking soda and salt on waxed paper. Beat butter, sugar and egg in largebowl till fluffy, about 3 minutes. Beat in hot water and vanilla. Graduallybeat in flour mixture until blended and smooth. Drop dough by well roundedteaspoonfuls on prepared baking sheets. Bake in 190ºC oven till golden,about 10 minutes. Cook on sheets on wire rack to cool completely.
Makes about 3 dozen cookies