Rinse wild rice under cold water. Combine rice and water in a pot, bring to a boil, then simmer for 45 minutes until grains split open. Set aside.
Cut chicken into bite-sized pieces. Cook gently in 2 tablespoons butter over medium-low heat until just cooked through. Measure 2 cups and set aside.
In the same pot, melt 6 tablespoons butter. Add onion and sauté until soft and translucent.
Stir in flour and cook for 1–2 minutes, stirring constantly, without browning.
Slowly add chicken broth while stirring. Bring to a gentle boil and let thicken.
Add carrots and cooked chicken. Reduce heat and simmer gently.
Toast slivered almonds in a dry pan over low heat until lightly golden. Set aside.
Stir most of the cooked wild rice into the soup.
Add evaporated milk, sherry, and toasted almonds. Heat gently until creamy and thick. Do not boil.
Adjust thickness with remaining rice if needed. Serve warm.