Cook spaghetti according to package directions in a 6-qt. stockpot. In a small saucepan, whisk eggs and cream until blended. Cook over low heat until a thermometer reads 160°, stirring constantly (do not allow to simmer). Remove from heat; stir in cheese.
Drain spaghetti; return to stockpot. Add sauce and bacon; toss to combine. Serve immediately. If desired, sprinkle with additional cheese.