In a large saucepan, heat 2 tablespoons of the oil over medium heat. Add the celery, carrots and onions, and sweat for 5 minutes while stirring. Add the lentils and cover with 2 inches of water. Stir in the bay leaf and bring to a boil, then reduce the heat and simmer for 30 to 35 minutes. Drain and season with salt and pepper. Discard the bay leaf and cool.
While the lentils are cooking, make the vinaigrette. Whisk together the balsamic vinegar, agave, red pepper, lemon juice and zest and some salt and pepper. Slowly stream in 3 tablespoons oil while continuously whisking. Pour the vinaigrette over the cooled lentils then fold in the diced avocado and cranberries. Pour into a bowl, garnish with the chopped parsley and serve.