Heat the oil in a saucepan over medium-high heat. Add the shallots, and cook until soft and translucent. Add the garlic and carrot, and cook for 3 minutes more, until the garlic is fragrant. Add 1/4 cup water along with the peas, and cook covered, on low heat, until the carrot is tender, about 8 minutes, then turn off the heat, and set aside until you’re ready to eat.
In a large bowl, gradually add a little hot liquid from the lamb to the peanut butter, mixing it with more and more liquid until it’s thick, smooth and pour-able. Return it all to the pot with the meat, and mix well.
Add the okra, Scotch bonnet and fish sauce, and simmer gently, uncovered, for about 30 minutes or so, stirring frequently to avoid clumps of peanut butter at the bottom of the pot, until the sauce is thick enough to coat a spoon and a little bit of fat has pooled at the top.
In a pot with a tightly fitted lid, bring 2 cups of salted water to a boil, add the fonio, stir, cover and turn off the heat. After 5 minutes, remove the lid and fluff with a fork. Fold fonio into the shallots and peas, season and taste.