Wash sage, shake dry and pluck leaves from the stems. Wash the legs, dab dry and divide at the joint. Remove the chicken skin from the meat in 2 places and insert a sage leaf in between each.
Season with salt and pepper. Spread in the greased fat pan of the oven and cook in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for approx. 45 minutes. For the sauce, wash and halve the tomatoes.
Clean, wash and cut the spring onions into rings. Heat oil. Fry the tomatoes and spring onions for about 2 minutes, turning them over, except for a little bit for garnishing. Add lentils and tomato paste after 1 minute.
Deglaze with stock, bring to the boil and simmer for about 15 minutes. In the meantime prepare noodles in boiling salted water according to package instructions. Arrange noodles, legs and sauce on plates. Garnish with spring onions.