Preheat oven to 350°F. Grease muffin tins or a bundt pan.
In a small saucepan, simmer chopped dates and water until soft (5–7 minutes). Let cool slightly, then blend into a purée.
In a large bowl, cream together softened butter, brown sugar, and vanilla until light. Beat in eggs one at a time. Add molasses and golden syrup.
In another bowl, whisk together flour, baking powder, and baking soda. Gently fold dry ingredients into wet mixture, alternating with date purée.
Pour batter into muffin tins or prepared pan. Bake muffins 18–20 min or bundt 55–60 min, until a toothpick comes out clean.
While baking, make sauce: In a saucepan, melt butter, brown sugar, cream, and golden syrup. Simmer until thickened (5–8 minutes).
Remove pudding from oven. While warm, pour some sauce over each portion. Reserve extra for serving.
Serve warm with vanilla ice cream, custard, or whipped cream.