MIX coconut milk and red curry paste in small saucepan. Bring to simmer on low heat, stirring constantly.
STIR in chicken stock, fish sauce, peanuts, sugar, salt, kaffir lime leaves and cornstarch mixture. Bring to simmer. Stirring constantly, simmer until mixture begins to thicken slightly. Remove from heat.
STIR in basil and chiles, if desired.