Instead of getting flavor from a ham hock, this mess of black-eyed peas and collards gets its smokiness from canned chipotles and caramelized shallots, thereby keeping it vegetarian.
Drain the soaked peas and rinse. Place in a large pot and add enough water to cover by 2 inches. Bring to a boil over high heat. Adjust heat to maintain a gentle simmer, cover and cook until tender, 30 to 45 minutes. (Alternatively, cook peas in a pressure cooker or slow cooker.) Reserve 1 1/2 cups of the cooking liquid and drain the peas.
Heat oil in the pot over medium heat. Add shallots and a pinch of salt and cook, stirring frequently, until deeply browned, 10 to 15 minutes. Use a slotted spoon to transfer half the shallots to a paper-towel-lined plate.
Add collards to the pot and toss until bright green and wilted, about 3 minutes. Add the reserved cooking liquid and chipotles. Bring to a boil. Adjust heat to maintain a simmer, cover and simmer for 15 minutes.
Gently stir in the peas. Cover and simmer until the collards are very tender, about 10 minutes more. Stir in lime juice and the remaining 1/2 teaspoon salt. Top with the shallots and serve with rice, if desired.
To make ahead: Refrigerate peas and reserved cooking liquid (Step 1) separately for up to 3 days.