If the cooker your using has a sauté function, use that. If not, heat a large skillet on medium high heat. Heat 2 tbsp olive oil . Add the eggplant cubes and cook, letting them sit undisturbed so they brown. Cook about 6–8 minutes until lightly golden. If cooking in a separate skillet, transfer to a slow cooker.
In the same pan, add the remaining 1 tbsp olive oil, along with the onion and carrot. Cook for about 5 minutes until softened.
Add the garlic, tomato paste, and fennel seeds if using. Cook 1–2 minutes until the tomato paste darkens slightly.
Pour in the red wine and scrape up any browned bits from the pan. Let the mixture simmer for about 2 minutes.
Transfer everything to the slow cooker.
Add the crushed tomatoes, lentils, vegetable broth, oregano, thyme, salt, pepper, red pepper flakes, and parmesan rind if using. Stir well.
Cook on LOW for 6–8 hours or HIGH for 3–4 hours, until the lentils are tender and the eggplant is very soft.
At the end of cooking, use an immersion blender to pulse part of the ragù directly in the pot, blending just enough to break down some of the eggplant and create a thicker, saucier texture.
Remove the parmesan rind.
Cook the pasta in well-salted water until al dente. Reserve 1–1½ cups of pasta water before draining.
Add the cooked pasta to the ragù along with ½ cup of grated Parmesan. Toss well, adding splashes of pasta water until the sauce becomes glossy and coats the pasta.
Stir in lots of freshly chopped basil right at the end.
To serve, spoon the pasta into bowls or on a large platter.
Top with torn burrata, a swirl of balsamic vinegar, freshly cracked black pepper, extra fresh basil, and a drizzle of olive oil.
