There's a chance this could be Tequila-Funny & Humor Color Changing Mug Morphing Coffee or Tea Mug Cup,11-Ounce

Description

Show your true colors with a morphing mug. Just plain black in color when it's cold, this magical 11 oz. mug will turn white and reveal your design only when filled with a hot beverage. Just add your coffee or tea, and watch your images come to life in vibrant color. 100% Ceramic. come in 11 Ounce with black handle.