I had so many of them 🙂 My husband is Dutch, so we spent (and still do) quite a lot of time in The Netherlands years before going vegan (we're together for almost 13 years, vegan for 6 years). He is from a village close to Den Bosch, so every weekend, we were queueing in front of Jan de Groot banket bakkerij to get them 😉
Oh, I have no idea if there are vegan ones. My sweet tooth sort of (almost) disappeared so I'm not triggered to look for pastries anymore 🙂
BUT, there are vegan worstenbroodjes! And they are so good! We let our family try and nobody noticed they were vegan 😂