Balkan Puzzle block uses 3 fabric, background, accent, plus one more. It is built entirely with half square triangles. Cut 1 strip 2 inches wide from each of the 3 fabrics.
Half Square Triangle instructions
Match 1 strip of background fabric to 1 of the other fabrics right sides together.
Using a side right triangle ruler or template, cut 8 half square triangles pairs each for background & accent as well as background & extra fabric. Move ruler/template upside down for next cut when necessary.
Sew ¼ inch seam on long side of triangle pair.
Press seam to one side.
Repeat with remaining triangle pairs.
Finishing up - Sew blocks together as shown in layout with ¼ inch seam allowance. Press seams to one side.