The spelling of the phrase "had one number" is a straightforward and phonetically sound process. In IPA phonetic transcription, it would be ['hæd wʌn ˈnʌmbər]. The pronunciation of the word "had" corresponds to the symbol /hæd/, while "one" is transcribed as /wʌn/. The final word "number" is pronounced as /ˈnʌmbər/. To spell this phrase, one must simply combine the individual phonemes of each word in their proper order. This grouping of phonemes into recognizable words is the foundation of the English language.