Char the peppers over an open flame, turning them frequently until completely blackened on all sides. Use tongs for this.
Transfer immediately to a glass or steel container. Cover and let them steam for 10 mins.
Meanwhile roast the walnuts in a dry pan until lightly browned and aromatic.
Once the peppers are cool enough to handle, peel away the blackened skin using your fingers. Pop out the stem and discard the seeds.
Add the peppers to a blender jar. Also add the walnuts, bread (roughly torn), garlic clove, lemon juice, sugar, salt, and half the quantity of tamarind. Blend to a smooth dip. Taste and add more tamarind if necessary.
To serve, dollop onto a plate and top with pomegranate clusters and a drizzle of olive oil.