This is such a cool tradition! My husband came up with it once when we were in college, eating our Easter dinner by ourselves at Red Lobster (we were too far away from family for a real dinner).
We eat fish and bread for breakfast (I will qualify that and say that I do sneak a bowl of cereal beforehand!).
Why? At the end of the gospel of John, Jesus is hanging out on the beach watching Peter and some buddies fish. Peter realizes that it's the Risen Lord calling to them, and he jumps out of the boat and swims to shore. Jesus prepares some fish and bread for them, and they eat together.
We fry up some fish on the stove and slice some french bread for our breakfast. We then read the story out of the Bible. It's a little wacky, but just another way for us to reinforce for our kids the Easter story.