Recipes on the composition of the “salad of the monks” (Capuchin monks) have been reported in Italy since the 17th century. Different wild edible plants were highly regarded as an important ingredient of this mixed salad. Among these, some species played a key role for both their taste and nutritional properties: Plantago coronopus L. (PC), Rumex acetosa L., Cichorium intybus L., and Artemisia dracunculus L. In the present study, the micromorphological and phytochemical features as well as the antioxidant and anti-inflammatory properties of extracts of these fresh and blanched leaves, were investigated. The extracts obtained by blanched leaves, according to the traditionally used cooking method, showed the highest content of bioactive compounds (total phenols 1202.31–10,751.88 mg GAE/100 g DW; flavonoids 2921.38–61,141.83 mg QE/100 g DW; flavanols 17.47–685.52 mg CE/100 g DW; proanthocyanidins 2.83–16.33 mg CyE/100 g DW; total chlorophyll 0.84–1.09 mg/g FW; carbohydrates 0.14–1.92 g/100 g FW) and possess the most marked antioxidant (IC50 0.30–425.20 µg/mL) and anti-inflammatory activity (IC50 240.20–970.02 µg/mL). Considering this, our results indicate that increased consumption of the investigated plants, in particular of PC, raw or cooked briefly, could provide a healthy food source in the modern diet by the recovery and enhancement of ancient ingredients.