Expeditious Retreat
You take the Dash action, and until the spell ends, you can take that action again as a Bonus Action.
Expeditious Retreat 5e 2024 vs. 2014 edition differences
The 2014 version allows taking the Dash action as a bonus action each turn, while the 2024 version lets you take the Dash action as your action and then again as a bonus action each turn until the spell ends. The 2024 version explicitly states the repeated Dash action, whereas the 2014 version implies it.