Preheat oven to 200C / 375F. Put the beetroot in a pan, rub in 2 tbsp of butter, salt and pepper, with the red wine. Roast for 40 minutes, turning occasionally. When soft, puree the whole thing and season to taste.
Rub inside of chicken with sage, salt and pepper. Put a sliver of butter in each piece (like, less than a teaspoon) and roll up. Wrap with pancetta and tuck the ends under so it stays put. In a pan that’s ok on on the stove and in the oven, heat up remaining butter and brown chicken. Put the whole hot pan in the oven and bake for 20-25 minutes.
Put the endives center up on a cookie sheet and drizzle with a little oil, salt and pepper. Roast under the grill until the leaves start to burn, about 20 minutes.