There is rarely one right answer. Here are several categories of pairing options, each with a reason it may work.
Walnut
Similar lightness for a subtle, tone-on-tone pairing with minimal contrast.
Coffee
Similar lightness for a subtle, tone-on-tone pairing with minimal contrast.
Taupe
Similar lightness for a subtle, tone-on-tone pairing with minimal contrast.
Chocolate Brown
Similar lightness for a subtle, tone-on-tone pairing with minimal contrast.
Grey
Enough lightness contrast to read as two distinct colours without feeling harsh.
Beaver
Enough lightness contrast to read as two distinct colours without feeling harsh.
Taupe Grey
Enough lightness contrast to read as two distinct colours without feeling harsh.
Clay
Enough lightness contrast to read as two distinct colours without feeling harsh.
Lime
A saturated accent from a different hue family for a deliberate pop of contrast.
Chartreuse
A saturated accent from a different hue family for a deliberate pop of contrast.
Spring Green
A saturated accent from a different hue family for a deliberate pop of contrast.
Yellow
A saturated accent from a different hue family for a deliberate pop of contrast.
White
Meets WCAG AA contrast (7.5:1) for normal text if used as text/background.
Ivory
Meets WCAG AA contrast (7.4:1) for normal text if used as text/background.
Mint Cream
Meets WCAG AA contrast (7.3:1) for normal text if used as text/background.
Azure
Meets WCAG AA contrast (7.3:1) for normal text if used as text/background.