Prepare the Fennel: Warm a splash of olive oil in a large skillet set over medium heat. Add the fennel wedges and cook for about 5-7 minutes, turning occasionally, until they are golden brown and tender. Season with salt and pepper.

Toast Fennel Seeds: In the same skillet, add the fennel seeds and toast them for about 1-2 minutes until fragrant. Set aside.

Sauté Cavolo Nero: Add a little more olive oil to the skillet if needed, and then add the cavolo nero. Sauté for 3-4 minutes until wilted and slightly crispy around the edges. Season with salt and pepper, then set aside with the fennel wedges.

Cook Lentils: In a separate pan, gently heat the boiled lentils with a drizzle of olive oil and a few sprigs of thyme. Stir in the lemon juice, zest, and fennel seeds. Season with salt and pepper, and heat through for about 3-4 minutes.

Combine Everything: Add the sliced fennel and cooked lentils into the skillet with the cavolo nero. Stir to combine and allow all the flavors to meld together for about 2 minutes. Remove from heat, and stir in the cold butter to add a rich, creamy finish.

Serve: Plate the mixture of fennel, lentils, and cavolo nero. Finish with a generous shaving of Parmesan cheese, the chopped fennel fronds, and a drizzle of olive oil. Add extra lemon juice and freshly cracked black pepper to taste.