Place beef in a bowl, season with salt and pepper and mix to combine. Form into 6 small finger shapes, place on an ungreased baking sheet.
Bake in the preheated oven until starting to brown, about 7 minutes.
Combine water, tahini, lemon juice, mixed spices, salt, and pepper in a bowl; whisk until tahini is dissolved and fluffy, about 5 minutes.
Transfer tahini mixture to a saucepan over low heat; cook and stir constantly until simmering, about 3 minutes. Add meat fingers to saucepan. Simmer, stirring occasionally, until meat is fully cooked and no longer pink inside, about 30 minutes. An instant-read thermometer inserted into the center should read at least 160 degrees F (70 degrees C).