Remove excess sand from clams by soaking them in a bowl of cold salted water. The clams will open up their shells and release any sand and grit that is inside.
In a pan, heat the 1/4 cup oil and fry up 2 cloves garlic, the chili pepper, the stone, if using, and cherry tomatoes until the tomatoes soften and lose their shape, about 3 minutes.
Add the clams, and cook for 30 seconds with the lid on, shaking the pan often.
Add the wine to the pan, and cover with the lid until the clams have completely opened.
The clams release some water, which is the base for the soup. Add a generous splash of white wine. You can make this more soupy by adding a little more wine or even a few spoonfuls of tomato puree.
Add the parsley and salt, to taste. Continue cooking for another minute for all the flavors to come together.
Rub some raw garlic on the toasted bread slices. Drizzle the bread with the extra virgin olive oil. Serve the clam soup in bowls with 2 half slices of toast per bowl.
*Make sure you remove the stone before serving.