In a food processor, process cookie crumbs until finely ground. In a small cup, dissolve espresso powder in 2 tsp water. Stir in liqueur. Add coffee liquid, butter and salt to cookie crumbs.

Blend well.

Line an 8 inch loaf pan with aluminum foil. Pat mixture firmly into pan and level top.

Chill fudge until firm, 2 hours.

Lift fudge from pan still on foil. Place on cutting board and cut into 24 pieces. Remove from foil and place between layers of wax paper in a tightly covered container. Store in refrigerator.