Saute onion and garlic
Stir in potato and carrot, cook until tender
If needed, add 1/4 c vegetable broth
Stir in celery and season
Thickened with flour mixture
Fill pancakes with filling, roll into rissoles shape
Dissolve a little flour, salt and water. Use this mixture to brush filled pancakes
Roll rissoles on breadcrumbs and fry in enough oil, on medium heat