Cheesy Mushroom Pull Apart Bread

For the Mushrooms 12 oz sliced mushrooms 1 Tbsp butter 1 Tbsp chopped fresh thyme For the Bread 1 unsliced loaf sourdough bread 12 ounces Provolone cheese, thinly sliced 1/2 cup butter, melted 1/2 cup finely diced green onion 2 teaspoons poppy seeds