Cook chorizo over medium high heat 5-6 minutes until cooked.
While chorizo is cooking, peel hard-boiled eggs and slice in half lengthwise.
Dig out egg yolks with teaspoon and place in a small bow.
Add mayonnaise, mustard and salt to mixture and combine thoroughly.
Fill cooked egg whites with chorizo mixture using a teaspoon (or frosting tip).
Top chorizo with egg yolk mixture.
Sprinkle with chopped cilantro, if desired.
Cover and refrigerate before serving.