Bring the stock to a boil in a medium saucepan, then reduce the heat and keep at abare simmer.
Melt 3 tablespoons butter with the olive oil in a large, heavy saucepanover medium heat.
Add the onion and cook, stirring constantly with a wooden spoon, until softened and translucent, about 3 minutes.
Add the rice and cook, stirring, for about 3 minutes, until every grain is coated with butter and oil.
Then add the wine and stir until absorbed.
Add 1 cup of the stock and stir until the liquid is absorbed.
Continue adding stock, about 1/2 cup at a time, stirring frequently and making sure all the liquid is absorbed before adding more stock.
Cook until the rice is just tender and creamy but still al dente, about 15 to 20 minutes.
You may have leftover stock.
Remove pan from heat and stir in the goat cheese, Parmesan, 3 tablespoons butterand the pears.
Cook over low heat until cheese just melts and pears are heatedthrough, about 1 1/2 minutes.
Season with salt and pepper, add the fresh thyme andtoasted walnuts, toss well and serve immediately.