The existence of a second Higgs doublet in Nature could lead to a cosmological first order electroweak phase transition and explain the origin of the matter-antimatter asymmetry in the Universe. We explore the parameter space of such a two-Higgs-doublet-model and show that a first order electroweak phase transition strongly correlates with a significant uplifting of the Higgs vacuum w.r.t. its Standard Model value. We then obtain the spectrum and properties of the new scalars $H_0$, $A_0$ and $H^{pm}$ that signal such a phase transition, showing that the decay $A_0 rightarrow H_0 Z$ at the LHC and a sizable deviation in the Higgs self-coupling $lambda_{hhh}$ from its SM value are sensitive indicators of a strongly first order electroweak phase transition in the 2HDM.
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