This mixed-methods one-shot study examines L2 writers' perceptions of using Automatic Speech Recognition (ASR) to write using the Technology Acceptance Model (TAM), based on three criteria: usefulness, ease of use, and intention to use. After receiving training on Google voice typing in Google Docs, 17 English as a Second Language (ESL) students carried out two ASR-based writing tasks over a two-hour period. After the treatment, participants filled in a TAM-informed survey and participated in semi-structured interviews to measure their perceptions based on the target criteria. Findings indicate positive perceptions of ASR as a writing tool in terms of usefulness (language learning potential) and ease of use (e.g. user-friendly voice commands). We believe that these positive perceptions might lead to an intention to continue to use ASR, suggesting that the technology has L2 pedagogical potential. [For the complete volume, "CALL and Professionalisation: Short Papers from EUROCALL 2021 (29th, Online, August 26-27, 2021)," see ED616972.]