If you were thinking of , the structure was different. While it featured high-stakes cooking, the central focus of that specific episode was a Japanese Elimination Test (sushi platter) following a team challenge, rather than a standalone Mystery Box.
In this episode, the contestants were surprised to learn they had to create a dish using provided under the box. This "must-use-all" rule significantly raised the stakes and forced the home cooks out of their comfort zones right at the start of the competition. Challenge Details [S3E13] Mystery Box Challenge 1
The search for "[S3E13] Mystery Box Challenge 1" suggests you are likely referring to , where the contestants faced a unique twist in their first major Mystery Box. Episode Summary If you were thinking of , the structure was different