The Scent of Scandal by Emma V. Leech

A penniless young lady, rescued by providence.

When Miss Fredericka Wycliffe’s eccentric Uncle Phin dies and leaves her all his worldly goods, she cannot believe her good fortune. A passionate missionary man, Phineas Wycliffe was not wealthy, but a little cottage in the Highlands of Scotland and a modest bequest seem like riches beyond Fredericka’s wildest dreams.
The catch.
To meet the terms of the will, Fredericka must swear on the bible to continue her uncle’s good works on his last and greatest challenge; to bring spiritual light into the dark world of her nearest neighbour, the Laird of the Moncreiffe clan who lives at the forbidding and half-ruined Tor Castle.

A man with scars, both visible and hidden.

Ross Moncreiffe is a hard man, and one best left alone. Raised through the ranks from lowly private to Captain of the Cameron Highlanders the war has left him scarred and angry. The last thing he wants is a priggish English miss living on his doorstep and trying to show him the error of his ways.
Vanilla and cinnamon.
Miss Wycliffe does not give her word lightly nor scare easily, however. Besides, tormenting this glowering, great Highlander is too delicious to resist. Something tells this intrepid miss that there’s more to the big Scot than meets the eye, and … just why does he always smell so good?
Ross is indeed hiding a surprising passion and one he’d rather die than reveal.

Let the battle of wills commence.