Apple Silicon Mini – Connecting to Apple Thunderbolt Display

HDMI is out because the Mac Mini's HDMI port maxes out at 1920x1200. You're going to need to grab an adapter to go from Mini-Displayport to either dual-link DVI or Displayport, which are both supported by the Dell.

Now, the Thunderbolt display can't directly output Mini-Displayport for boring technical reasons (see question 20). There must be a non-display Thunderbolt device between the display and the adapter I mentioned above. The cheapest example I've found is the Seagate GoFlex Desk Thunderbolt Adapter (STAE122), which has two Thunderbolt ports for daisychaining and retails for about $180.

The full chain:
Mac Mini -> Thunderbolt Display -> STAE122 -> MiniDP to DP or DL-DVI adapter -> Dell monitor

Yes, that will work just fine.