First make the breadcrumb topping. In a non-stick skillet, melt butter over medium heat. Add bread cubes & stir constantly until all cubes are a toasty brown. Set aside.
Drain peas & pour into an 8x8 dish. Spread evenly. Next, layer the cream of mushroom soup & spread evenly to cover the peas. Then, slice or chop the eggs & spread an even layer over the cream of mushroom soup. Next layer the cheese slices evenly over the top of the eggs. Finally, add the breadcrumb topping & spread evenly over the top of the casserole.
Bake at 350 degrees for approximately 30 minutes, or until the cheese is melted & the casserole starts to bubble.
