Wash and peel the potatoes, then dice them into small cubes.
Chop the carrots and onions into similar-sized pieces.
In a large pot, melt the butter over medium heat.
Add the onions and sauté until they turn translucent.
Stir in the diced potatoes and carrots, cooking for about 5 minutes.
Pour in the milk and add the salt and pepper.
Bring the mixture to a simmer, then reduce the heat to low.
Add the green beans and corn, stirring gently to combine.
Cover the pot and let it simmer for 20 minutes, stirring occasionally.
Once the vegetables are tender, remove from heat and garnish with fresh herbs.