Heat the oil in a small saucepan over high heat. When the oil is hot, add the corn kernels, the corncob, shallots, garlic, salt, and pepper and sautÈ for 2 to 3 minutes. Stir in the stock and saffron and cook for 2 minutes.
Stir in the cream and simmer until the sauce is thick enough to coat a spoon, for about 6 to 7 minutes. Discard the corncob and whisk in the butter. Remove from the heat and whisk until the butter is thoroughly incorporated, or prepare except for the butter and store, refrigerated, in an airtight container for up to 24 hours. Reheat the sauce over low heat, whisk in the butter, and proceed from there.
Yield: about 2 cups