Break each matzo square into about 8 pieces; place in a medium bowl. Add enough boiling water to cover, and soak until moistened, 2 or 3 minutes; drain. Squeeze well with hands to remove excess water.
In a medium bowl, beat eggs with nutmeg and 1/2 teaspoon salt; add softened matzo, and mix.
Heat 1 tablespoon butter in an 8-inch nonstick skillet over medium heat, swirling to coat; add matzo mixture, and press in gently. Cook until browned on underside, 4 to 6 minutes; carefully invert cake onto a plate. Heat remaining tablespoon butter in skillet, and slide cake back into skillet. Cook until other side is browned, 4 to 6 minutes more.
Turn cake out of skillet, and cut into wedges. Serve hot.