In a small bowl, combine the warm water and active dry yeast. Stir gently and let it sit for 5 to 10 minutes until the mixture is foamy.
In a large mixing bowl, whisk together the kefir and honey until combined.
Add the foamy yeast mixture to the kefir mixture and stir to combine.
Add 2 1/2 cups of the flour and the salt to the wet ingredients. Stir with a wooden spoon or dough hook until a sticky dough forms.
Gradually add the remaining 1/2 cup flour, a little at a time, kneading the dough either by hand on a floured surface or with a mixer fitted with a dough hook. Knead for about 8 to 10 minutes until the dough is smooth and elastic but still slightly tacky.
Lightly grease a large bowl with 1 tablespoon of the melted butter. Place the dough in the bowl and turn to coat it with butter.
Cover the bowl with a clean kitchen towel or plastic wrap and let the dough rise in a warm, draft-free place for about 1 hour or until doubled in size.
Preheat the oven to 375°F (190°C).
Punch down the risen dough to release the air. Shape it into a loaf and place it into a greased 9×5-inch loaf pan.
Brush the top of the dough with the remaining 1 tablespoon of melted butter.
Cover the loaf pan loosely with a kitchen towel and let the dough rise again for 20 to 30 minutes until it has risen slightly above the edge of the pan.
Bake the bread in the preheated oven for 30 to 35 minutes, or until the top is golden brown and the bread sounds hollow when tapped.
Remove the bread from the oven and let it cool in the pan for 10 minutes. Then transfer it to a wire rack to cool completely before slicing.