I have four models: Vegetables, Fruits, Herbs and Condiments. Each model has separate collection view, and different cell identifier. Data is successfully fetched which I confirmed by printing number of objects. I have used DiffableDataSource, where data source is initialized as follows: Source & snapshot: var dataSource: UICollectionViewDiffableDataSource<String, NSManagedObjectID>? typealias DataSource = UICollectionViewDiffableDataSource<String, NSManagedObjectID> typealias Snapshot = NSDiffableDataSourceSnapshot<String, NSManagedObjectID> Setting up data source: private func setupDataSource<T:NSManagedObject>(for collectionView:UICollectionView, with identifier: String, of entity: T.Type) ->DataSource { let dataSource = DataSource( collectionView: collectionView, cellProvider: {(collectionView, indexPath, managedObjectID) -> UICollectionViewCell? in let cell = collectionView.dequeueReusableCell(withReuseIdentifier: identifier, for: indexPath) as! KitchenCollectionViewCell if let pantry = try? self.kitchenCoreDataStack.managedContext.existingObject(with: managedObjectID) as? T { self.configure(cell: cell, for: pantry) } return cell }) return dataSource } When breakpoint is set in above code, it doesn't go past this line: cellProvider: {(collectionView, indexPath, manageObjectID) Snapshot code to reflect changes: extension KitchenViewController: NSFetchedResultsControllerDelegate{ func applySnapshot(animatingDifferences: Bool){ let snapshot = Snapshot() dataSource?.apply(snapshot, animatingDifferences: animatingDifferences) } } I called datasource function with : dataSource = setupDataSource(for: firstCollectionView, with: "fruits", of: Fruits.self)