Wash and peel the carrots and cut them into small pieces (e.g. cubes or crescents).
Boil 1 liter of water, add salt and sugar. Then boil the chopped carrots in water for about 5 - 10 minutes until they are soft.
1 minute before the carrots are ready to cook, add the frozen peas to the boiling water.
Remove 2 ladles from the cooking water, then drain the vegetables and rinse with ice-cold water.
Melt 2 tablespoons butter in a small pan over a low flame. Toast 1 teaspoon flour in the butter, stirring constantly with a flat whisk. When the roux is golden yellow, gradually add the cooking water while stirring - until a creamy, thick sauce is formed.
Mix the vegetables with the sauce. Round off the whole thing with salt and pepper, depending on your taste.