In a bowl, combine the minced meat, soaked bun, egg, mustard, garlic, parsley, marjoram, salt, and pepper. Knead well and shape into small balls.
Heat oil in a pan over medium-high heat and fry the meatballs for 3-4 minutes until lightly browned on all sides.
In a saucepan, melt butter over medium heat. Add diced onions and carrots and simmer for 3-4 minutes until softened.
Slowly pour in Moscatel wine and bring to a boil over medium-high heat. Remove from heat, stir in a splash of cream, and blend with a hand blender until smooth.
Add the meatballs to the sauce and simmer gently over low heat for 10 minutes.