Preheat the oven to 350 degrees F. Butter and flour a six 1-cup nonstick mini bundt pan.
Whisk confectioners sugar, 3 tablespoons milk, and vanilla until smooth. Add more milk 1 teaspoon at a time, if needed. Drizzle over cakes, garnish with sliced almonds and let stand for 30 minutes.
*Nutritional information is an estimate. Please consult a doctor or nutritionist for the most accurate nutritional info.