Tex. Health & Safety Code § 437B.152

A mobile food vendor who seeks to serve food or beverages that may require the vendor's reclassification shall notify the department of the nature of the food or beverages to be sold. The department, or a local authority in a collaborative agreement with the department under Section 437B.153, may conduct a health inspection and reclassify the vendor in accordance with the rules adopted under Section 437B.151.