In 10-inch skillet, cook bacon over medium heat 8 to 10 minutes, turning occasionally, until crisp and brown. Remove from skillet; drain on paper towels. Crumble bacon.
Meanwhile, in 2-quart saucepan, heat 1 inch water to boiling. Add potatoes. Cover; heat to boiling. Reduce heat to medium-low. Cook covered 6 to 8 minutes or until potatoes are tender; drain. In medium bowl, beat eggs, milk, salt and pepper with fork or wire whisk until well mixed; set aside.
In 10-inch skillet, melt butter over medium-high heat. Cook potatoes in butter 3 to 5 minutes, turning potatoes occasionally, until light brown. Stir in onions. Cook 1 minute, stirring constantly.
Pour egg mixture into skillet. As mixture begins to set at bottom and side, gently lift cooked portions with metal spatula so that thin, uncooked portion can flow to bottom. Avoid constant stirring. Cook 3 to 4 minutes or until eggs are thickened throughout but still moist. Sprinkle with crumbled bacon.