Puree sweet potato, chickpeas, red wine vinegar, olive oil, garlic, salt and pepper, making sure that there is enough acid from the vinegar to balance out the sweet potatoes. Also check for salt.
Mix the dijon mustard and honey. Generously salt the avocado and egg slices. You may also wish to coat the avocado with lemon juice to prevent browning.
Assemble the sandwiches: Slather both pieces of bread with the honey mustard. On one side, generously spread the sweet potato mixture. Add the salad greens, avocado, pickled red onions, and egg. Top with the other piece of bread. Slice and serve.