Mix flour, salt, and baking powder to blend. Cut in cream cheese till it is size of peas. Cut in butter till it is the size of butterbeans. Add vinegar and toss it around. Now add the cream starting with 2 tablespoons, then add the rest 1 tablespoon at a time. Press dough into a ball. Flatten into a disc and wrap, refrigerate at least 1 hour before rolling.