Heat oven to 350 degrees F. Lightly coat a roasting pan with vegetable cooking spray.
Arrange the cod fillets skin-side down. Sprinkle with the chili powder, oregano, and salt. Roast 5 to 7 minutes or until the cod is just opaque and flakes when tested with a fork.
Meanwhile, melt the butter in a small skillet over medium-low heat. Cook, swirling constantly, just until the butter begins to brown. Add the cumin and lime juice and continue to cook, swirling 1 minute longer.
Remove the cod from the oven. Set aside half the cod for Day 3. Drizzle the cumin-lime butter over the remaining cod and serve with the potatoes and peas.
Place sweet potatoes in a large saucepan and cover with salted water. Bring to a boil. Reduce heat, cover, and simmer 10 to 12 minutes or until fork-tender. Drain. Add the zest, juice, butter and a dash of salt.
Beat with an electric mixer until the potatoes are light and fluffy.
Place sugar snap peas in a steamer and steam until tender but still crisp, about 4 minutes. Toss with mint, season, and serve.