Horn OK Please is an Indian vegetarian and vegan street food takeaway stall selling moong dal dosa, samosa chaat, bhel puri and masala chai. It sits behind the Royal Festival Hall at the Southbank Centre Food Market on Belvedere Road, near Waterloo station. The moong dal dosa and masala chai are made to order in front of you. The dosa comes as a masala dosa topped with potato and chickpeas or as a moong dal dosa with added chilli and paneer, while the chaat and chai portions are small.