Cook the spaghetti according to package directions.
While the spaghetti cooks, prepare the sauce.
Heat the butter in a pan. Add the onion, carrot and ham. Cook until the carrot pieces are done.
Add the peas. Pour in the milk.
Cut (or tear) the cream cheese into tiny pieces and drop directly into the pan.
Cook everything together with occasional stirring just until the sauce simmers and the cream cheese pieces are melted.
Taste the sauce. Season with salt and pepper.
Add the cooked spaghetti to the sauce and toss well.
Serve the spaghetti with ham, veggies and white sauce at once.