For the assembly:
1/4 cup unsalted butter, melted
1/2 cup breadcrumbs
1/2 cup sugar
1. Dissolve yeast in tepid water, which is water with a temperature anywhere between 100 and 110 degrees F. To proof yeast, add 1 teaspoon sugar and let stand for 10 minutes. If the mixture doubles in volume then yeast is active.
2. In a large bowl, whisk together the flour, sugar and salt. Add the milk, melted butter, eggs, and yeast and combine well. On a clean surface dusted with flour, knead the mixture into a smooth elastic dough. Add more flour, if necessary.
3. Let the dough rest in a bowl greased lightly with canola oil. Cover the bowl with plastic wrap and let the dough rise until the size doubles, about three hours.
4. Divide the dough into two equal parts. Shape each part into a log and divide into eight equal parts with each piece weighing about 2-1/2 ounces. Roll each piece into a 3- by 5-inch rectangular sheet. Brush with melted butter, sprinkle with breadcrumbs and sugar, and roll the sheet like you would a jelly roll. Start from one corner and roll towards the opposite corner. Then sprinkle the rolled dough with more breadcrumbs and sugar. Place the pieces with the seam-side down on a greased baking sheet.
5. Preheat the oven to 375 degrees F. Let the rolls rise for another 30 minutes. Bake until golden brown, about 15 minutes.
Spanish bread freezes very well. Toss a frozen roll in the microwave and reheat for 30 seconds.