Dissolve yeast and 1 tsp. sugar into warm water, and set aside to proof -- in a few minutes, the yeast should create a floating layer of foam.
In a small saucepan, heat cream and butter until the butter has entirely melted.
Once butter has mostly melted, add in the sugar and salt, and stir in thoroughly.
Let sour cream mixture cool until only slightly warm.
In large bowl, slightly beat the eggs, and blend in the yeast mixture.
Once sour cream mixture has cooled, add to egg mixture and blend thoroughly. (Pour in a thin stream, stirring it in as you pour.)
With a spatula, mix in the flour, one cup at a time.
Cover bowl loosely with plastic wrap, and let rise until doubled in volume.
Butter/grease either two medium (6 cup / 8.5" x 4.5") loaf pans or one bundt pan (12 cup / 10" x 3.5").
Preheat oven to 350 degrees F.
Stir down dough and pour into prepared pan(s), and let rise again until doubled.
Bake 30 - 35 minutes.