Pour stock into a medium saucepan, add mushroom powder and heat until simmering. Cover and keep warm.
Heat the oil in a heavy, large saucepan over medium heat.
Add mushrooms to pan and sauté until lightly browned
Add rice and shallot along with a little salt and pepper and sauté until shallots are translucent.
Stir in the garlic and sauté for 30 seconds.
Stir in 1 cup of hot broth, stirring until liquid is absorbed.
Add soy sauce, fish sauce and miso.
Add another cup of hot broth, stirring until liquid is absorbed. Up until this point, the risotto can be made 4 hours ahead. Refrigerate the risotto (the rice will still be firm) and remaining broth, uncovered, until cool, then cover and keep them refrigerated until ready to proceed.
Bring the remaining broth to a simmer.
Cover and keep it warm over very low heat.
Stir 1 cup of hot broth into the partially cooked risotto over medium heat, stirring until the broth is absorbed and the risotto is hot.
Add the remaining broth. Simmer and stir until the rice is just tender and the mixture is creamy, about 5 minutes longer.
The result should be creamy and somewhat pourable and the rice should be firm but without a crunchy center. If the rice is still underdone, add ¼ cup very hot water and stir until creamy. Repeat as necessary.
Season to taste with soy sauce, fish sauce and black pepper.
*We made our mushroom powder by grinding dried mushrooms in a coffee grinder. A spice grinder would work equally well.