Preheat the oven to 180 degrees C. Put the carrots in a roasting dish and toss with 1 tablespoon of olive oil and sprinkle with salt and pepper. Put in the oven for 20 minutes.
Cut the beef into bite size pieces. After the carrots have been in the oven for 20 minutes, add the beef and cook for another 10 minutes.
Make the dressing by whisking together the honey, mustard, vinegar and oil in a bowl.
When the beef and carrots are done, tip them into a large bowl along with any cooking juices. Add the lentils and dressing and stir.
To serve, pile the salad into bowls and top with salad leaves.