These proceedings summarise recent work in which the Standard Model and New Physics form factors of $\Lambda_{b} \rightarrow \Lambda_{c} \ell^{-} \bar{\nu}_{\ell}$ decays were computed up to order $\mathcal{O}(\Lambda^{2}_{\rm QCD} / m^{2}_{c})$ using Heavy Quark Effective Theory (HQET). This allowed for a subsequent HQET-based determination of form factors of the decay using a fit, which combines recent theoretical predictions and experimental measurements. Consequently, the most precise value of $R(\Lambda_{c})$ to date was determined, $R(\Lambda_{c})=0.324 \pm 0.004$. Additionally, the sensitivity of $R(\Lambda_{c})$ to potential NP interactions was explored.