Toss the cherry tomatoes with olive oil and salt. Roast at 400 F for 20-25 minutes, until tomatoes are blistered and slightly caramelized. Set aside to cool.
In a food processor or blender, combine white beans, lemon juice, minced garlic, olive oil and salt. Add 3/4 of the roasted cherry tomatoes. Blend until smooth. Add water if mixture is too thick.
To serve, spoon into a shallow bowl and top with remaining roasted cherry tomatoes.