Sandwich and cake formats of interventionist Dynamic Assessment suffer from two problems: both are time-demanding, and the intervention presented to the learners varies from one learner to another. To suggest a solution to the above problems in teaching and assessing reading strategies, the present researchers have introduced ‘sauce’-format mediation through which intervention is provided for the learners within ‘mediation boxes’ along the test. Thirty Iranian intermediate EFL learners participated in the study. They were first given a non-mediated reading pretest, and then they took the same test along with a ‘mediation box’ following each question to observe the probable effect of ‘sauce’-format mediation. To measure the transcendence of the given mediation, the participants answered a non-mediated delayed posttest at the end. Comparing the means of the mediated posttest and non-mediated pretest on the one hand and those of the non-mediated delayed posttest and the pretest on the other revealed that the learners benefitted significantly well from the ‘sauce’-format mediation and could transfer their learning to a novel context. Findings of this study are consistent with the previous research on DA that intervention supports learner development. Manuscript profile