Toast the bread slices and keep aside.
Apply mayo on one side for two pieces of toast (hereafter referred as single sided mayo toast) and on both sides for the other 2 pieces of toast (hereafter referred as double sided mayo toast).
Take one of the single sided mayo toast. Spread chicken filling on the mayo side. Make sure the filling is spread evenly. Top that with one of the double sided mayo toast. Press gently.
Spread sliced cucumber and tomato on top of the second bread slice. Top it with remaining double sided mayo toast. Press gently.
Slice the fried egg into four and place it on top of the third piece of toast. Cover the fried egg with the remaining single sided mayo toast. Press gently.
Cut the sandwich into triangles using a serrated knife. Hold the sandwich together with a tooth pick or a wooden skewer.