Preheat the oven to 450F or 425F convection. Line a baking sheet with parchment paper.
Add cabbage wedges and carrots to the baking sheet. Drizzle the oil mostly over the cabbage and a little bit over the carrots. Sprinkle evenly with ½ teaspoon salt and pepper. Rub the oil and salt all over each cabbage wedge, then toss the carrots to coat.
Arrange the cabbage wedges and carrots evenly on the baking sheet. Nestle the sausage between the veggies (see note on sausage). Bake for 25-30 minutes or until cabbage is beginning to char and sausage is browned.
Meanwhile, in a medium pot, add the lentils and fill with enough water to cover by about 2 inches. Bring to a boil over high heat, then reduce the heat to medium-low to maintain a rapid simmer for 15 minutes, or until the lentils are cooked through (time to cook can vary, use your judgment). Drain and transfer back to the pot. Stir in the dijon, vinegar, and remaining ½ teaspoon salt until combined. Cover and set aside.
In a jar with a lid, add all of the dressing ingredients and shake vigorously to combine.
Assemble your bowls! Add warm lentils, roasted veg, and sausage to your bowl. Top with cheese, nuts, herbs, and drizzle generously with the dressing.
Eating tips! Use a fork and a sharp knife to cut up the cabbage, then mix everything together. I also like to break the sausage into smaller pieces so I get more sausage bites.