Heat oven to 350°F.
Mix shortening, butter, sugar, eggs and vanilla thoroughly.
Measure flour by dipping method or by sifting.
Blend together flour and salt; stir in.
Roll dough into balls (1 tsp. per ball).
Beat egg white slightly with fork.
Dip balls in egg white; roll in nuts.
Place about 1” apart on engrossed baking sheet; press thumb gently in center of each.
Bake at 350°F for 10-12 minutes or until set. Cool. Fill thumbprints with jelly.