Sometimes, non-native English speakers sound "too correct" when they pronounce every sound in the word because native speakers are taking shortcuts. This is one of those shortcuts.
Consonants CAN create their own syllables. Consonants that create their own syllables are called “syllabics.”
The consonants /m, n, ŋ, l/ can be used as a syllable without a vowel when they follow a consonant made in the same position (the tongue is in the same place in the mouth) and they are in the unstressed syllable of the word.
The most common syllabics are made with the /n/, the syllabic-N.
4-page pdf with examples and link to video descriptions