Prunus spinosa L., commonly known as blackthorn, holds traditional significance both as a food source and an herbal remedy. This study aims to determine the extract that includes the highest total phenolic content (TPC), antioxidant capacity (AC) using DPPH and CUPRAC assays, and vitamin C from blackthorn using the response surface method in an ultrasonic water bath and to this extract into powder by foam mat drying. The investigation comprises two primary phases. Firstly, the impact of temperature (20–80 °C) and extraction time (5–30 min) on TPC, AC, and vitamin C were systematically explored. Subsequently, the extracts derived from blackthorn fruit were subjected to foam mat drying, utilizing two distinct ratios (7:3 w/w and 8:2 w/w) of foaming agents [maltodextrin (MD) to egg white (EW)], along with three drying techniques (oven, microwave, and natural drying). The optimized extraction parameters were determined as follows: temperature (80 °C) and time (30 min). Furthermore, the results reveal that microwave-dried powders with a low EW ratio exhibit superior preservation of TPC, AC, and vitamin C content. This research underscores the potential utility of foam mat-dried blackthorn powders as functional ingredients and natural colorants within the realm of the food industry.